Merge branch 'master' into fix/issue-790-slice-a-heartbeat-policy

2026-07-23 19:52:27 -05:00 · 2026-07-23 19:13:01 -05:00 · 2026-07-23 12:31:44 -05:00 · 2026-07-23 01:13:11 -05:00 · 2026-07-23 00:06:18 -05:00 · 2026-07-22 04:19:48 -04:00
23 changed files with 1980 additions and 6696 deletions
@@ -163,7 +163,19 @@ _TERMINAL_OWNERSHIP_STATUSES = frozenset(
    {"released", "abandoned", "done", "blocked", "terminal", "closed"}
 )
 _EXPIRED_STATUSES = frozenset({"expired"})
-_STALE_STATUSES = frozenset({"stale", "stale_dead_process", "stale_missing_worktree"})
+_STALE_STATUSES = frozenset(
+    {
+        "stale",
+        "stale_dead_process",
+        "stale_missing_worktree",
+        # #790 Slice A heartbeat-lifecycle bands. Listed here so they are
+        # *classified* rather than falling through to the unknown-status branch;
+        # they still block unless the ownership record proves
+        # ``reclaim_allowed is True``, so the O2 fail-closed rule is unchanged.
+        "stale_missed_heartbeat",
+        "stale_absolute_cap",
+    }
+)


 def _norm_str(value: Any) -> str:
@@ -525,90 +537,6 @@ def assess_ownership_record_activity(record: dict[str, Any]) -> dict[str, Any]:
    }


-# Reviewer-lease reclaim is only reachable from a non-live (expired/stale) lease.
-_RECLAIMABLE_REVIEWER_STATUSES = _EXPIRED_STATUSES | _STALE_STATUSES
-
-
-def is_active_ownership_status(status: str | None) -> bool:
-    """True when *status* denotes live/active ownership of a branch (#855).
-
-    Used to decide whether a *competing* active claimant still uses a branch
-    when weighing an expired reviewer lease for reclaim. Expired, stale,
-    released, and terminal statuses are not active.
-    """
-    return _norm_str(status).lower() in _ACTIVE_OWNERSHIP_STATUSES
-
-
-def assess_expired_reviewer_lease_reclaim(
-    *,
-    role: str,
-    status: str,
-    pr_merged: bool | None,
-    owner_pid_alive: bool | None,
-    competing_active_claimant: bool | None,
-) -> dict[str, Any]:
-    """Decide, explicitly and fail-closed, whether an expired reviewer lease
-    may stop protecting an already-merged branch (#855 AC4).
-
-    An expired reviewer lease should not protect a merged branch forever once
-    its work is done and no live claimant remains. Reclaim is permitted only
-    when **every** condition below is provably satisfied; any unknown
-    (``None``) or contrary value keeps the lease protective:
-
-    - the lease is a ``reviewer`` lease (author/merger/controller/reconciler
-      leases are out of scope and always keep protecting);
-    - its status is expired or stale (never an active/live lease);
-    - the PR is proven merged (``pr_merged is True``);
-    - the lease owner process is proven dead (``owner_pid_alive is False``);
-    - no competing active claimant uses the branch
-      (``competing_active_claimant is False``).
-
-    Returns a decision dict with ``reclaim_allowed`` and, when refused, the
-    fail-closed ``reasons``. The reasons never contain secrets — only the
-    role, the status, and which condition was unproven.
-    """
-    reasons: list[str] = []
-    normalized_role = _norm_str(role).lower()
-    normalized_status = _norm_str(status).lower()
-
-    if normalized_role != "reviewer":
-        reasons.append(
-            f"lease role '{normalized_role or 'unknown'}' is not a reviewer "
-            "lease; expired-reviewer reclaim does not apply"
-        )
-    if normalized_status not in _RECLAIMABLE_REVIEWER_STATUSES:
-        reasons.append(
-            f"lease status '{normalized_status or 'unknown'}' is not expired "
-            "or stale; only a non-live reviewer lease may be reclaimed"
-        )
-    if pr_merged is not True:
-        reasons.append(
-            "PR merged state is not proven true; reclaim requires an "
-            "already-merged PR (fail closed)"
-        )
-    if owner_pid_alive is not False:
-        reasons.append(
-            "lease owner process liveness is not proven dead; a live owner "
-            "still protects the branch (fail closed)"
-        )
-    if competing_active_claimant is not False:
-        reasons.append(
-            "a competing active claimant may still use the branch; reclaim "
-            "requires no other active ownership (fail closed)"
-        )
-
-    allowed = not reasons
-    return {
-        "reclaim_allowed": allowed,
-        "role": normalized_role,
-        "status": normalized_status,
-        "decision": (
-            "reclaim_expired_reviewer_lease" if allowed else "keep_protecting"
-        ),
-        "reasons": [] if allowed else reasons,
-    }
-
-
 def assess_active_branch_ownership(
    *,
    remote: str,
@@ -1,223 +0,0 @@
-# ADR: MCP restart governance and authorization policy
-
- **Status:** Accepted (policy effective immediately for LLM and operator sessions; enforcement tooling may lag)
- **Date:** 2026-07-23
- **Tracking issue:** [#656](https://gitea.prgs.cc/Scaled-Tech-Consulting/Gitea-Tools/issues/656)
- **Policy version:** `restart-governance/v1`
- **Related:**
-  - Umbrella: [#655](https://gitea.prgs.cc/Scaled-Tech-Consulting/Gitea-Tools/issues/655) — governed MCP restart coordination and zero-disruption recovery
-  - Vision: [#652](https://gitea.prgs.cc/Scaled-Tech-Consulting/Gitea-Tools/issues/652) — MCP Control Plane Web Console product vision (§A system health and process control)
-  - Roadmap: [#653](https://gitea.prgs.cc/Scaled-Tech-Consulting/Gitea-Tools/issues/653) — Control Plane Web Console phased delivery (Phase 2 restart controls)
-  - Contamination guard: [#630](https://gitea.prgs.cc/Scaled-Tech-Consulting/Gitea-Tools/issues/630) — blocks manual process-kill recovery
-  - Console restart UX: [#642](https://gitea.prgs.cc/Scaled-Tech-Consulting/Gitea-Tools/issues/642) — sanctioned restart and graceful reload
-  - Existing restart / reconnect paths to inventory: [#591](https://gitea.prgs.cc/Scaled-Tech-Consulting/Gitea-Tools/issues/591) — auto-restart on master advance (closed); [#584](https://gitea.prgs.cc/Scaled-Tech-Consulting/Gitea-Tools/issues/584) — host auto-reconnect on transport flap
-  - Stable-control runtime split: `docs/architecture/mcp-stable-control-runtime-policy-adr.md` (#615)
-  - Client-namespace health: `docs/mcp-namespace-health.md` (#543)
-  - Reconnect-only EOF recovery: `docs/mcp-namespace-eof-recovery.md`
-
-## 1. Context
-
-The Gitea MCP server is the **control plane** for real issue and PR mutations
-(create, comment, lock, review, merge, reconcile). The same process serves every
-role namespace (`gitea-author`, `gitea-reviewer`, `gitea-merger`,
-`gitea-reconciler`, `gitea-controller`) and holds the in-memory capability-gate
-code loaded at startup.
-
-Restarting that process is destructive to concurrent work:
-
- It resets every session's identity, preflight, and capability-lease binding.
- It can interrupt a mutation mid-critical-section (a lock acquire, a review
-  submit, a merge), leaving durable state half-written.
- Relaunching from the wrong checkout or worktree silently changes which code
-  the control plane runs, defeating master-parity gates (#420 / #615).
-
-Today there is **no durable written policy** stating who may restart MCP, under
-what conditions, that restart is a last resort, and how controller approval,
-automated safety gates, and break-glass interact. Operators and LLM sessions
-therefore invent restart behavior ad hoc, which makes concurrent multi-role work
-unsafe. #630 and #642 need this policy as their backbone.
-
-This ADR defines that policy. It does **not** implement coordinator code or HA
-multi-instance restart (those are later children of #655).
-
-## 2. Decision
-
-### 2.1 v1 decision (recorded)
-
-**Restart authority in v1 is `controller approval + automated safety gates`.**
-
-A restart of the stable control runtime is authorized only when **both** hold:
-
-1. A **controller** role explicitly approves the restart, recording an audit
-   entry (who, why, scope, affected sessions), **and**
-2. The **automated safety gates** pass: a completed drain acknowledgement (no
-   affected session is mid-critical-section) or a declared break-glass incident
-   (§2.5).
-
-Quorum among multiple controllers is **not** required day-one. It is deferred
-unless a later investigation (tracked under #653) proves single-controller
-approval is insufficient. This ADR records the v1 decision so enforcement code
-(#630) has a fixed target; changing it requires a superseding ADR.
-
-### 2.2 Restart is a last resort — the recovery ladder
-
-Restart is the **last** rung. Before any restart, exhaust the narrower
-recoveries, in order:
-
-1. **Reconnect** the IDE/client MCP namespace (transport EOF, `client is
-   closing: EOF`, transient `#584` flap). No process change. See
-   `docs/mcp-namespace-eof-recovery.md`.
-2. **Refresh / rebind** the session workspace: re-run `gitea_whoami`,
-   `gitea_resolve_task_capability`, and pass an explicit validated
-   `worktree_path`. Fixes stale session context without touching the process.
-3. **Scoped restart** of a single misbehaving namespace/service (where the
-   deployment supports per-service restart) rather than the whole control plane.
-4. **Full restart** of the stable control runtime process — operator-owned,
-   controller-approved, drained.
-5. **Host / infrastructure restart** — the broadest action; same authorization
-   as a full restart plus infrastructure ownership.
-
-A session **must** try rungs 1–2 and record why they were insufficient before
-requesting a restart at rung 3 or above. Skipping straight to restart is a
-policy violation.
-
-### 2.3 Authorization matrix
-
-| Role | Reconnect (1) | Refresh/rebind (2) | Scoped restart (3) | Full restart (4) | Host restart (5) |
-|---|---|---|---|---|---|
-| **author** | self | self | request only | **forbidden** | forbidden |
-| **reviewer** | self | self | request only | **forbidden** | forbidden |
-| **merger** | self | self | request only | **forbidden** | forbidden |
-| **reconciler** | self | self | request only | **forbidden** | forbidden |
-| **controller** | self | self | **approve** (+gates) | **approve** (+gates) | request to operator |
-| **operator** | self | self | execute (controller-approved) | execute (controller-approved) | execute (controller-approved) |
-| **admin** | self | self | execute | execute | execute (break-glass) |
-
-Legend: *self* = may perform for its own client session; *request only* = may
-raise a restart request but not authorize or execute it; *approve* = may
-authorize under §2.1 gates; *execute* = may perform the process action after the
-authorization is recorded.
-
-Key invariants:
-
- **No LLM worker role (author/reviewer/merger/reconciler) may perform or
-  authorize a full or host restart.** They may only reconnect/rebind their own
-  client and file a restart request.
- **Controller approval authorizes; operator/admin executes.** The approving
-  controller and the executing operator may be the same human, but both the
-  approval and the execution are audited.
- Privileged process actions (full restart, host restart) are reserved to
-  **operator/admin**, never to an automated worker.
-
-### 2.4 Approved conditions
-
-A restart at rung 3+ is approved only under one of these recorded conditions:
-
- **No affected sessions:** the control plane has no live session that would be
-  interrupted (verified, not assumed).
- **Full drain acknowledged:** every affected session has drained
-  (no open critical section — no held mutation lease mid-write) and the drain is
-  acknowledged in the audit record.
- **Controller + gates:** controller approval plus passing automated safety
-  gates (§2.1), the standard v1 path.
- **Quorum:** not required in v1; reserved for a future superseding ADR.
- **Break-glass:** an incident-backed emergency exception (§2.5).
-
-Restart **never** bypasses mutation gates mid-critical-section. Drain before
-restart is mandatory except under break-glass with a declared incident.
-
-### 2.5 Break-glass
-
-Break-glass is a **separate, narrower** authorization path for emergencies where
-the normal drain-and-approve path cannot complete (e.g. the control plane is
-wedged and cannot drain).
-
-Break-glass conditions:
-
- A declared incident record exists (id, timestamp, declarer) **before** the
-  action.
- The action is taken by **operator or admin** authority only — never by an LLM
-  worker role, and never unilaterally by an operator with active peers when a
-  controller is reachable.
- The scope is the minimum necessary rung of the ladder.
- A **mandatory post-hoc audit** entry is filed: what was restarted, why the
-  normal path was impossible, which sessions were affected, and the incident id.
-
-Break-glass suspends the drain requirement, not the audit requirement.
-
-### 2.6 Explicit prohibitions
-
- **A unilateral LLM or operator full restart while active peer sessions
-  exist is forbidden.** An LLM worker role must not kill, restart, or relaunch
-  the MCP process; a lone operator must not full-restart over live peer work
-  without controller approval or a break-glass incident.
- Process-kill recovery is forbidden as a routine tool (#630). This ADR does not
-  introduce a kill path.
- Ambiguous policy state **denies** restart (§4).
-
-## 3. Security requirements
-
- Full restart and host restart are **privileged**; only operator/admin execute
-  them, only after a controller approval or break-glass incident is recorded.
- Break-glass is a distinct authorization path with its own audit mandate; it is
-  never the default and never silent.
- **Every approval and every restart action is audited** (who approved, who
-  executed, scope, affected sessions, condition, policy version). No restart is
-  authorized without a durable audit entry.
-
-## 4. Failure behavior
-
-**Ambiguous policy → deny restart.** If it cannot be established that a
-restart is authorized under §2 — unknown affected-session state, missing
-controller approval, absent break-glass incident, or an unclassifiable request —
-the safe action is to **refuse** the restart and stop with a recovery report,
-never to restart on assumption.
-
-## 5. Policy IDs (for enforcement code)
-
-Enforcement code — the restart coordinator (a later child of #655), the #630
-contamination guard, and the #642 console restart UX — binds to these stable
-policy identifiers rather than to prose:
-
-| Policy ID | Statement |
-|---|---|
-| `RG-01` | Restart is last resort; rungs 1–2 must be tried and recorded first (§2.2). |
-| `RG-02` | v1 authority = controller approval + automated safety gates (§2.1). |
-| `RG-03` | No LLM worker role performs or authorizes full/host restart (§2.3). |
-| `RG-04` | Full/host restart executed by operator/admin only, post approval (§2.3). |
-| `RG-05` | Drain before restart is mandatory except break-glass with incident (§2.4). |
-| `RG-06` | Break-glass requires a pre-declared incident and post-hoc audit (§2.5). |
-| `RG-07` | Unilateral LLM/operator full restart with active peers is forbidden (§2.6). |
-| `RG-08` | Ambiguous policy state denies restart (§4). |
-
-The `restart-governance/v1` **policy version** field is emitted on future
-restart audit events so approvals can be reconciled against the policy revision
-in force.
-
-## 6. Dogfooding
-
-Gitea-Tools governs its own MCP control plane by this policy. Author, reviewer,
-merger, and reconciler sessions operating on this repository use the recovery
-ladder (§2.2) — reconnect and rebind, never self-restart — and any real restart
-of the Gitea-Tools stable control runtime follows the controller-approval +
-drain path defined here.
-
-## 7. Acceptance and cross-links
-
-This ADR is the authoritative restart-governance policy. It **must** stay
-cross-linked from the safety model and the web-console deployment boundary:
-
- `docs/safety-model.md` § Process restart governance references this ADR.
- `docs/webui-deployment.md` references this ADR for restart/reload disposition.
-
-It is linked to its issue lineage — umbrella **#655**, vision **#652**, roadmap
-**#653**, contamination guard **#630**, and console restart UX **#642** — in
-§ Related above.
-
-## 8. Non-goals
-
- Implementing the restart coordinator or approval state machine (#630, later
-  children of #655).
- Implementing HA multi-instance restart or quorum machinery.
- Introducing any process-kill or auto-restart tool; existing auto-restart
-  behavior must be inventoried before any new restart tool is enabled.
@@ -100,6 +100,7 @@ that gates each call, not which tools exist.
 - `gitea_get_profile`
 - `gitea_get_runtime_context`
 - `gitea_get_shell_health`
+- `gitea_heartbeat_issue_lock`
 - `gitea_heartbeat_reviewer_pr_lease`
 - `gitea_inspect_workflow_lease`
 - `gitea_issue_irrecoverable_provenance_authorization`
@@ -46,17 +46,3 @@ If shell helpers are unavailable and MCP commit cannot run, stop with a recovery
 report (restart session, clear hung terminals, use MCP-native commit). See
 [`llm-workflow-runbooks.md`](llm-workflow-runbooks.md) § MCP-native commit path
 (#260) and agent temp artifact cleanup (#261).
-
-## 7. Process restart governance
-
-Restarting the MCP control-plane process is destructive to concurrent multi-role
-work and is governed by a dedicated policy. Restart is a **last resort** behind
-narrower recoveries (reconnect, rebind), full/host restart is reserved to
-operator/admin under **controller approval + automated safety gates**, a
-unilateral LLM or operator full restart with active peers is **forbidden**, and
-ambiguous policy state **denies** restart. Break-glass is a separate,
-incident-backed path with a mandatory audit.
-
-See [`architecture/mcp-restart-governance.md`](architecture/mcp-restart-governance.md)
-(#656) for the authorization matrix, the recovery ladder, break-glass
-conditions, and the `RG-01`–`RG-08` policy IDs.
@@ -55,15 +55,6 @@ shipped to the browser.
 assumption paths, and the client-secret policy. Use it to verify an instance is
 configured for internal-only operation.

-## Process restart / reload disposition
-
-The console never exposes a restart or reload control; process restart of the
-MCP control-plane runtime is governed separately. Restart is a last resort behind
-reconnect/rebind, full restart is operator/admin-only under controller approval
-plus safety gates, and break-glass is an incident-backed path. See
-[`architecture/mcp-restart-governance.md`](architecture/mcp-restart-governance.md)
-(#656).
-
 ## Non-goals (MVP)

 - Full SSO or session login in the UI
@@ -440,32 +440,13 @@ def _session_author_lock_worktree() -> str | None:

    Used to derive the author mutation workspace when no explicit
    ``worktree_path`` or env binding is provided. Never invents a path.
-
-    #864: a session pointer whose owner PID is dead and is not this process
-    must not force workspace binding for other issues — rebind is required for
-    that issue, and a stale dead-owner pointer must not poison unrelated work.
    """
    try:
        lock = issue_lock_store.read_session_issue_lock() or {}
    except Exception:
        return None
    path = (lock.get("worktree_path") or "").strip()
-    if not path:
-        return None
-    pid = lock.get("session_pid")
-    if pid is None:
-        pid = lock.get("pid")
-    try:
-        pid_i = int(pid) if pid is not None else None
-    except (TypeError, ValueError):
-        pid_i = None
-    if (
-        pid_i is not None
-        and pid_i != os.getpid()
-        and not issue_lock_store.is_process_alive(pid_i)
-    ):
-        return None
-    return path
+    return path or None


 def _resolve_preflight_workspace_path(worktree_path: str | None = None) -> str:
@@ -2039,6 +2020,7 @@ import allocator_dependencies  # noqa: E402
 import dependency_graph  # noqa: E402  # #784 durable dependency edges
 import control_plane_db  # noqa: E402
 import lease_lifecycle  # noqa: E402
+import lease_policy  # noqa: E402
 import workflow_dashboard  # noqa: E402  # #605 live queue/lease dashboard
 import incident_bridge  # noqa: E402
 import sentry_observability  # noqa: E402  (#606 optional Sentry observability)
@@ -2050,7 +2032,6 @@ import issue_lock_store  # noqa: E402
 import issue_lock_adoption  # noqa: E402
 import issue_lock_recovery  # noqa: E402
 import issue_lock_renewal  # noqa: E402
-import dirty_same_claimant_session_rebind  # noqa: E402  # #864
 import stacked_pr_support  # noqa: E402
 import merge_approval_gate  # noqa: E402
 import review_quarantine  # noqa: E402  # #695 contaminated formal-review quarantine
@@ -2282,7 +2263,6 @@ import canonical_comment_validator as ccv  # noqa: E402
 # GITEA_ISSUE_LOCK_DIR, bound to the current MCP session via a per-PID pointer.
 # Legacy global path retained only for test/doc references — do not seed manually.
 ISSUE_LOCK_FILE = "/tmp/gitea_issue_lock.json"
-WORK_LEASE_TTL_HOURS = 4
 AUTHOR_ISSUE_WORK_LEASE = "author_issue_work"
 VALID_WORK_LEASE_OPERATIONS = frozenset({
    AUTHOR_ISSUE_WORK_LEASE,
@@ -2445,20 +2425,6 @@ def _evaluate_issue_lock_recovery(
            descendant_sha=local_head,
        )

-    # #871: the inverse of the #768 descendant relation — the *remote* head may
-    # have advanced past the local/recorded head via a sanctioned merge-based
-    # branch sync (``gitea_update_pr_branch_by_merge``) while the local worktree
-    # stayed put. Observe that provenance server-side so the assessor can prove
-    # it and nothing else. Probed only when the heads differ; never from any
-    # caller-supplied value.
-    sync_provenance: dict | None = None
-    if remote_head and local_head and remote_head != local_head:
-        sync_provenance = issue_lock_worktree.read_merge_sync_provenance(
-            worktree_path,
-            prior_head_sha=local_head,
-            synced_head_sha=remote_head,
-        )
-
    # #772: with no remote branch there is no head to measure against, so the
    # base the branch was cut from is observed instead. Probed only in that
    # case, so the published path's evidence is untouched (#772 AC8).
@@ -2501,7 +2467,6 @@ def _evaluate_issue_lock_recovery(
        remote_branch_exists=remote_branch_exists,
        recorded_base_sha=recorded_base,
        base_ancestry=base_ancestry,
-        sync_provenance=sync_provenance,
    )


@@ -2597,7 +2562,12 @@ def _build_author_issue_work_lease(
    host: str | None,
 ) -> dict:
    created = _work_lease_now()
-    expires = created + timedelta(hours=WORK_LEASE_TTL_HOURS)
+    # #790 Slice A: the window comes from the central policy, not a literal here.
+    # It is also now a *sliding* window — the lease lives ``initial_ttl_minutes``
+    # past its last valid heartbeat rather than a fixed four hours past its
+    # creation, so an abandoned task stops holding the claim within one TTL.
+    policy = lease_policy.policy_for(lease_policy.TASK_CLASS_AUTHOR_ISSUE_WORK)
+    expires = created + timedelta(minutes=policy.initial_ttl_minutes)
    return {
        "operation_type": AUTHOR_ISSUE_WORK_LEASE,
        "issue_number": issue_number,
@@ -2608,6 +2578,15 @@ def _build_author_issue_work_lease(
        "created_at": _work_lease_timestamp(created),
        "expires_at": _work_lease_timestamp(expires),
        "last_heartbeat_at": _work_lease_timestamp(created),
+        # #790 AC-N1: the ownership key for this task. Distinct from the recorded
+        # PID, which is the shared daemon and identifies no individual task.
+        "task_session_id": issue_lock_store.mint_task_session_id(
+            AUTHOR_ISSUE_WORK_LEASE
+        ),
+        # #790 AC-N8: the explicit lifecycle marker. Its absence — never a
+        # timestamp comparison — is what makes a lock legacy.
+        "lifecycle_version": lease_policy.LIFECYCLE_HEARTBEAT_V1,
+        "heartbeat_count": 1,
    }


@@ -4378,260 +4357,135 @@ def gitea_lock_issue(


@mcp.tool()
-def gitea_rebind_dirty_same_claimant_author_session(
+def gitea_heartbeat_issue_lock(
    issue_number: int,
    branch_name: str,
-    worktree_path: str,
-    old_pid: int,
-    expected_local_head: str,
-    expected_remote_head: str,
-    expected_dirty_paths: list[str],
-    expected_fingerprints: dict,
+    task_session_id: str | None = None,
    remote: str = "dadeschools",
    host: str | None = None,
    org: str | None = None,
    repo: str | None = None,
-    dry_run: bool = False,
-    authorize_reconciler_execute: bool = False,
+    worktree_path: str | None = None,
+    expected_generation: int | None = None,
 ) -> dict:
-    """Rebind a dirty registered issue worktree to this session (#864).
+    """Prove an owned author issue lease is still active (#790 Slice A).

-    Sanctioned only when every pin agrees: same claimant, dead old_pid matching
-    the durable lock, matching local/remote heads, exact dirty path set, and
-    per-path sha256 fingerprints. Preserves every tracked/untracked byte.
-    Does not sync remote, create recovery worktrees, clean, reset, or move heads.
+    The task-liveness signal the lifecycle was missing. Before this, an author
+    lease carried a fixed four-hour expiry that nothing could shorten, and the
+    only liveness evidence was the recorded PID — the long-lived MCP daemon,
+    which stays alive across every task it serves and so proved nothing about
+    whether the authoring task still held the work.

-    Role gate:
-    * author — must match the lock claimant identity/profile
-    * reconciler — execute only when ``authorize_reconciler_execute=True``
-    * reviewer/merger — always refuse
+    Each successful call slides the lease ``initial_ttl_minutes`` past *now*
+    from the central policy, so an actively heartbeating session is never
+    evicted while an abandoned one releases its claim within one TTL.

-    ``gitea.issue.comment`` (author map entry) is required for mutation; dry_run
-    still assesses fully but writes nothing. Permission alone is never ownership
-    proof — every pin is re-checked server-side.
+    What this tool cannot do, by construction:
+
+    * **Acquire.** It refuses when no durable lock exists.
+    * **Take over.** Exact issue, branch, realpath-normalized worktree,
+      claimant username, claimant profile, and recorded task-session identifier
+      must all match; a superseded session holding an older identifier is
+      refused.
+    * **Revive.** A lease already past its grace is not heartbeatable — that
+      would let a session restore ownership it had stopped proving. It must use
+      the sanctioned reclaim path, which mints a new generation.
+
+    A lock predating the heartbeat lifecycle is rebound rather than heartbeated:
+    its exact owner is re-verified and a genuine task-session identifier and
+    first heartbeat are minted (#790 AC-N8). The rebind is decided server-side
+    from the durable lifecycle marker; there is no caller-facing switch.

    Args:
-        issue_number: Tracking issue number on the durable lock.
-        branch_name: Exact locked branch name.
-        worktree_path: Registered dirty worktree path (must be under branches/).
-        old_pid: Dead owner PID recorded on the lock (must match session_pid/pid).
-        expected_local_head: Full local HEAD sha the caller observed.
-        expected_remote_head: Full remote-tracking HEAD sha the caller observed.
-        expected_dirty_paths: Exact set of dirty relative paths (tracked+untracked).
-        expected_fingerprints: Map of relative path -> sha256 hex of file bytes.
+        issue_number: The locked issue number.
+        branch_name: The branch recorded on the lock.
+        task_session_id: The identifier this session received when it acquired
+            or rebound the lock. It is a fencing token, not an ownership
+            assertion: it is compared against durable state and can only ever
+            cause a refusal, never grant anything. Omitted only when rebinding a
+            legacy lock, which has no identifier yet and mints one.
        remote: Known instance — 'dadeschools' or 'prgs'.
-        host/org/repo: Optional target overrides (validated against binding).
-        dry_run: When true, assess only (no lock/session writes).
-        authorize_reconciler_execute: Reconciler-only execute gate.
+        host: Override the Gitea host.
+        org: Override the owner/organization.
+        repo: Override the repository name.
+        worktree_path: Author worktree recorded on the lock.
+        expected_generation: Optional fencing value. The per-issue flock already
+            serializes the read and the write, so this is for a caller that
+            wants to pin the generation it last observed across calls; a moved
+            generation fails closed.
+
+    Returns:
+        dict with 'success', 'performed', the sliding 'expires_at',
+        'last_heartbeat_at', 'lock_generation', 'task_session_id', the applied
+        'policy', and post-write 'freshness'; on refusal 'success'/'performed'
+        False with 'reasons' naming exactly what did not match.
    """
-    role = _profile_role_kind(get_profile())
-    role_norm = (role or "").strip().lower()
-
-    # Permission: authors need comment; dry_run assess is reachable under read
-    # for diagnosis, but execute always needs comment. Reconciler execute also
-    # needs comment when authorized.
-    if dry_run:
-        read_block = _profile_operation_gate("gitea.read")
-        if read_block:
-            return {
-                "success": False,
-                "dry_run": True,
-                "reasons": read_block,
-                "permission_report": _permission_block_report("gitea.read"),
-            }
-    else:
-        blocked = _profile_permission_block(
-            task_capability_map.required_permission(
-                "rebind_dirty_same_claimant_author_session"
-            ),
-            issue_number=issue_number,
-            remote=remote,
-            host=host,
-            org=org,
-            repo=repo,
-            org_explicit=org is not None,
-            repo_explicit=repo is not None,
-        )
-        if blocked:
-            return blocked
-
-    if role_norm in {"reviewer", "merger"}:
-        return {
-            "success": False,
-            "dry_run": bool(dry_run),
-            "outcome": dirty_same_claimant_session_rebind.REFUSED,
-            "reasons": [
-                f"role '{role_norm}' cannot rebind dirty same-claimant author "
-                "sessions (fail closed)"
-            ],
-        }
-    if role_norm == "reconciler" and not authorize_reconciler_execute and not dry_run:
-        return {
-            "success": False,
-            "dry_run": False,
-            "outcome": dirty_same_claimant_session_rebind.REFUSED,
-            "reasons": [
-                "reconciler role requires authorize_reconciler_execute=True "
-                "to execute dirty same-claimant rebind (fail closed)"
-            ],
-        }
+    blocked = _profile_permission_block(
+        task_capability_map.required_permission("heartbeat_issue_lock"),
+        issue_number=issue_number,
+        remote=remote,
+        host=host,
+        org=org,
+        repo=repo,
+        org_explicit=org is not None,
+        repo_explicit=repo is not None,
+    )
+    if blocked:
+        return blocked

+    resolved_worktree = issue_lock_worktree.resolve_author_worktree_path(
+        worktree_path, _canonical_local_git_root()
+    )
    h, o, r = _resolve(remote, host, org, repo)
-    try:
-        identity = _authenticated_username(h)
-    except Exception:
-        identity = None
-    profile = get_profile()
-    profile_name = profile.get("profile_name")
+    claimant = _work_lease_claimant(h)
+    identity = claimant.get("username")
+    profile = claimant.get("profile")

    existing = _load_existing_issue_lock(
        remote=remote, org=o, repo=r, issue_number=issue_number
    )
-    resolved_wt = os.path.realpath(os.path.abspath((worktree_path or "").strip()))
-    inv = dirty_same_claimant_session_rebind.collect_dirty_inventory(resolved_wt)
+    if not existing:
+        return {
+            "success": False,
+            "performed": False,
+            "issue_number": issue_number,
+            "reasons": [
+                f"no durable lock for issue #{issue_number}; heartbeat cannot "
+                "acquire a claim (fail closed)"
+            ],
+        }

-    branch_res = subprocess.run(
-        ["git", "-C", resolved_wt, "branch", "--show-current"],
-        capture_output=True,
-        text=True,
-        check=False,
-    )
-    current_branch = (branch_res.stdout or "").strip() or None
-    head_res = subprocess.run(
-        ["git", "-C", resolved_wt, "rev-parse", "HEAD"],
-        capture_output=True,
-        text=True,
-        check=False,
-    )
-    local_head = (head_res.stdout or "").strip() if head_res.returncode == 0 else None
-
-    # Observe remote-tracking head without network when possible.
-    remote_head = None
-    for ref in (
-        f"refs/remotes/origin/{branch_name}",
-        f"origin/{branch_name}",
-        f"refs/remotes/{remote}/{branch_name}",
-        f"{remote}/{branch_name}",
-    ):
-        rh = subprocess.run(
-            ["git", "-C", resolved_wt, "rev-parse", "--verify", "--quiet", ref],
-            capture_output=True,
-            text=True,
-            check=False,
+    if issue_lock_store.is_legacy_lease(existing):
+        # AC-N8 exit route one: canonical exact-owner rebinding. The other exit
+        # is terminal retirement, which is Slice B.
+        outcome = issue_lock_store.rebind_legacy_lock(
+            remote=remote,
+            org=o,
+            repo=r,
+            issue_number=issue_number,
+            branch_name=branch_name,
+            worktree_path=resolved_worktree,
+            identity=identity,
+            profile=profile,
+            expected_generation=expected_generation,
        )
-        if rh.returncode == 0 and (rh.stdout or "").strip():
-            remote_head = (rh.stdout or "").strip()
-            break
-    if remote_head is None:
-        # Fall back to caller's pin only for observation absence — assessment
-        # still requires pin==observed, so missing observation fails closed.
-        remote_head = None
+        outcome["operation"] = "legacy_rebind"
+        return outcome

-    # Competing live locks (other issues / other worktrees).
-    competing_live = []
-    for entry in issue_lock_store.list_live_locks():
-        competing_live.append(entry)
-
-    # Session pointers that claim this issue lock.
-    competing_sessions = []
-    lock_dir = issue_lock_store.default_lock_dir()
-    lock_path = issue_lock_store.lock_file_path(
-        remote=remote, org=o, repo=r, issue_number=issue_number, lock_dir=lock_dir
-    )
-    try:
-        for name in os.listdir(lock_dir):
-            if not name.startswith("session-") or not name.endswith(".json"):
-                continue
-            ptr = issue_lock_store.read_lock_file(os.path.join(lock_dir, name))
-            if not ptr:
-                continue
-            ptr_lock = str(ptr.get("lock_file_path") or "").strip()
-            if not ptr_lock:
-                continue
-            try:
-                same = os.path.realpath(ptr_lock) == os.path.realpath(lock_path)
-            except OSError:
-                same = ptr_lock == lock_path
-            if not same:
-                continue
-            try:
-                sess_pid = int(str(name)[len("session-") : -len(".json")])
-            except ValueError:
-                sess_pid = ptr.get("pid")
-            competing_sessions.append(
-                {
-                    "pid": sess_pid,
-                    "lock_file_path": ptr_lock,
-                    "live": issue_lock_store.is_process_alive(sess_pid),
-                }
-            )
-    except OSError:
-        pass
-
-    # Best-effort workflow-lease scan: any live lock file whose work_lease is a
-    # non-author workflow lease on this issue/branch counts as active.
-    workflow_lease_active = False
-    for path in issue_lock_store.iter_lock_files(lock_dir):
-        rec = issue_lock_store.read_lock_file(path)
-        if not rec:
-            continue
-        lease = rec.get("work_lease") if isinstance(rec.get("work_lease"), dict) else {}
-        op = str(lease.get("operation_type") or "")
-        if op and op != issue_lock_store.AUTHOR_ISSUE_WORK_LEASE:
-            if rec.get("issue_number") == issue_number or str(
-                rec.get("branch_name") or ""
-            ) == branch_name:
-                if issue_lock_store.is_lease_live(rec):
-                    workflow_lease_active = True
-                    break
-
-    repo_root = _canonical_local_git_root()
-    # permission_allowed reflects profile gate only — never ownership proof.
-    permission_allowed = True
-
-    result = dirty_same_claimant_session_rebind.apply_dirty_same_claimant_session_rebind(
+    outcome = issue_lock_store.heartbeat_session_lock(
        remote=remote,
        org=o,
        repo=r,
        issue_number=issue_number,
        branch_name=branch_name,
-        worktree_path=resolved_wt,
-        claimant_identity=identity,
-        claimant_profile=profile_name,
-        old_pid=old_pid,
-        expected_local_head=expected_local_head,
-        expected_remote_head=expected_remote_head,
-        expected_dirty_paths=list(expected_dirty_paths or []),
-        expected_fingerprints=dict(expected_fingerprints or {}),
-        existing_lock=existing,
-        current_identity=identity,
-        current_profile=profile_name,
-        role_kind=role_norm or role,
-        current_pid=os.getpid(),
-        current_branch=current_branch,
-        local_head=local_head,
-        remote_head=remote_head,
-        dirty_inventory=inv,
-        competing_live_locks=competing_live,
-        competing_sessions=competing_sessions,
-        workflow_lease_active=workflow_lease_active,
-        authorize_reconciler_execute=bool(authorize_reconciler_execute),
-        permission_allowed=permission_allowed,
-        repo_root=repo_root,
-        dry_run=bool(dry_run),
-        lock_dir=lock_dir,
+        worktree_path=resolved_worktree,
+        identity=identity,
+        profile=profile,
+        task_session_id=str(task_session_id or ""),
+        expected_generation=expected_generation,
    )
-    result["observed"] = {
-        "local_head": local_head,
-        "remote_head": remote_head,
-        "current_branch": current_branch,
-        "dirty_paths": inv.get("dirty_paths"),
-        "fingerprints": inv.get("fingerprints"),
-        "identity": identity,
-        "profile": profile_name,
-        "role_kind": role_norm,
-    }
-    return result
+    outcome["operation"] = "heartbeat"
+    return outcome


@mcp.tool()
@@ -11131,9 +10985,6 @@ def _collect_branch_ownership_records(
    """
    records: list[dict] = []
    inventory_error = False
-    # #855 AC4: expired/stale reviewer-lease records eligible for an explicit
-    # reclaim decision, evaluated after the full ownership inventory is built.
-    reviewer_reclaim_candidates: list[tuple[dict, bool | None]] = []
    target_branch = (branch or "").strip()
    if not target_branch:
        return {"records": records, "inventory_error": False}
@@ -11282,28 +11133,15 @@ def _collect_branch_ownership_records(
                else:
                    status = freshness_status
                    reclaim_allowed = False
-                rec = _base_rec(
-                    category=category,
-                    status=status,
-                    reclaim_allowed=reclaim_allowed,
-                    role=role,
-                    host=lease_host or host_n or host,
+                records.append(
+                    _base_rec(
+                        category=category,
+                        status=status,
+                        reclaim_allowed=reclaim_allowed,
+                        role=role,
+                        host=lease_host or host_n or host,
+                    )
                )
-                records.append(rec)
-                # #855 AC4: a reviewer lease that is expired/stale (its owner
-                # gone) becomes a candidate for an explicit, fail-closed
-                # reclaim decision made once the full inventory is known.
-                if (
-                    role == "reviewer"
-                    and status
-                    in branch_cleanup_guard._RECLAIMABLE_REVIEWER_STATUSES
-                ):
-                    owner_alive = (
-                        fr.get("owner_pid_alive") if isinstance(fr, dict) else None
-                    )
-                    reviewer_reclaim_candidates.append(
-                        (rec, owner_alive if isinstance(owner_alive, bool) else None)
-                    )
    except Exception:
        # O1: fail closed on control-plane inventory errors.
        inventory_error = True
@@ -11374,44 +11212,6 @@ def _collect_branch_ownership_records(
            )
        )

-    # #855 AC4: decide, explicitly and fail-closed, whether any expired/stale
-    # reviewer lease may stop protecting an already-merged branch. This runs
-    # only after the full ownership inventory is built, so a competing active
-    # claimant (an active lease, author session, worktree binding, or active
-    # reviewer comment lease) is visible. An inventory failure keeps every
-    # reclaim candidate protective (reclaim_allowed stays False).
-    if reviewer_reclaim_candidates and not inventory_error:
-        pr_merged_state: bool | None = None
-        if pr_number is not None and auth and base_api:
-            try:
-                pr_live = api_request(
-                    "GET", f"{base_api}/pulls/{int(pr_number)}", auth
-                )
-                if isinstance(pr_live, dict) and pr_live:
-                    pr_merged_state = bool(
-                        pr_live.get("merged") or pr_live.get("merged_at")
-                    )
-            except Exception:
-                # Unknown merged state fails closed (candidate stays protective).
-                pr_merged_state = None
-        for cand_rec, owner_alive in reviewer_reclaim_candidates:
-            competing = any(
-                other is not cand_rec
-                and branch_cleanup_guard.is_active_ownership_status(
-                    other.get("status")
-                )
-                for other in records
-            )
-            decision = branch_cleanup_guard.assess_expired_reviewer_lease_reclaim(
-                role=str(cand_rec.get("role")),
-                status=str(cand_rec.get("status")),
-                pr_merged=pr_merged_state,
-                owner_pid_alive=owner_alive,
-                competing_active_claimant=competing,
-            )
-            cand_rec["reclaim_allowed"] = decision["reclaim_allowed"]
-            cand_rec["reclaim_decision"] = decision["decision"]
-
    return {"records": records, "inventory_error": inventory_error}


@@ -11474,7 +11274,6 @@ def gitea_reconcile_merged_cleanups(
    dry_run: bool = True,
    execute_confirmed: bool = False,
    limit: int = 50,
-    pr_number: int | None = None,
    remote: str = "dadeschools",
    host: str | None = None,
    org: str | None = None,
@@ -11485,11 +11284,7 @@ def gitea_reconcile_merged_cleanups(
    Args:
        dry_run: Defaults to True. When True, only builds the reconciliation report.
        execute_confirmed: Must be True when dry_run=False.
-        limit: Max number of closed PRs to inspect (batch mode only; ignored when
-            ``pr_number`` is set).
-        pr_number: Optional exact merged PR selector (#855). When set, only that
-            PR is assessed/acted on (fail closed if missing, unmerged, or
-            ambiguous). When omitted, existing batch behaviour is preserved.
+        limit: Max number of closed PRs to inspect.
        remote: Known Gitea instance ('dadeschools' or 'prgs').
        host: Override the Gitea host.
        org: Override the owner/organization.
@@ -11524,120 +11319,11 @@ def gitea_reconcile_merged_cleanups(
                "audit_phase": audit_reconciliation_mode.current_phase(),
            }

-    # #855: optional exact PR pin. Fail closed before any inventory mutation.
-    exact_pr: int | None = None
-    if pr_number is not None:
-        try:
-            exact_pr = int(pr_number)
-        except (TypeError, ValueError):
-            return {
-                "success": False,
-                "performed": False,
-                "executed": False,
-                "dry_run": bool(dry_run),
-                "selection_mode": "exact_pr",
-                "selected_pr_number": pr_number,
-                "reasons": [
-                    f"pr_number={pr_number!r} is not a valid integer "
-                    "(fail closed; no mutation)"
-                ],
-                "blocker_kind": "invalid_pr_number",
-            }
-        if exact_pr <= 0:
-            return {
-                "success": False,
-                "performed": False,
-                "executed": False,
-                "dry_run": bool(dry_run),
-                "selection_mode": "exact_pr",
-                "selected_pr_number": exact_pr,
-                "reasons": [
-                    f"pr_number={exact_pr} must be a positive integer "
-                    "(fail closed; no mutation)"
-                ],
-                "blocker_kind": "invalid_pr_number",
-            }
-
    h, o, r = _resolve(remote, host, org, repo)
    auth = _auth(h)
    base = repo_api_url(h, o, r)
-
-    selection_mode = "batch"
-    closed_prs: list[dict] = []
-    open_prs: list[dict] = []
-    if exact_pr is not None:
-        selection_mode = "exact_pr"
-        try:
-            pr_live = api_request("GET", f"{base}/pulls/{exact_pr}", auth)
-        except Exception as exc:
-            return {
-                "success": False,
-                "performed": False,
-                "executed": False,
-                "dry_run": bool(dry_run),
-                "selection_mode": selection_mode,
-                "selected_pr_number": exact_pr,
-                "reasons": [
-                    f"PR #{exact_pr} could not be uniquely resolved "
-                    f"(fail closed; no mutation): {_redact(str(exc))}"
-                ],
-                "blocker_kind": "pr_unresolvable",
-            }
-        if not isinstance(pr_live, dict) or not pr_live:
-            return {
-                "success": False,
-                "performed": False,
-                "executed": False,
-                "dry_run": bool(dry_run),
-                "selection_mode": selection_mode,
-                "selected_pr_number": exact_pr,
-                "reasons": [
-                    f"PR #{exact_pr} could not be uniquely resolved "
-                    "(empty response; fail closed; no mutation)"
-                ],
-                "blocker_kind": "pr_unresolvable",
-            }
-        live_number = pr_live.get("number")
-        try:
-            live_number_int = int(live_number) if live_number is not None else None
-        except (TypeError, ValueError):
-            live_number_int = None
-        if live_number_int != exact_pr:
-            return {
-                "success": False,
-                "performed": False,
-                "executed": False,
-                "dry_run": bool(dry_run),
-                "selection_mode": selection_mode,
-                "selected_pr_number": exact_pr,
-                "reasons": [
-                    f"PR #{exact_pr} resolution is ambiguous or mismatched "
-                    f"(live number={live_number!r}; fail closed; no mutation)"
-                ],
-                "blocker_kind": "pr_ambiguous",
-            }
-        if not (pr_live.get("merged") or pr_live.get("merged_at")):
-            return {
-                "success": False,
-                "performed": False,
-                "executed": False,
-                "dry_run": bool(dry_run),
-                "selection_mode": selection_mode,
-                "selected_pr_number": exact_pr,
-                "reasons": [
-                    f"PR #{exact_pr} is not merged "
-                    "(exact-target cleanup requires a merged PR; "
-                    "fail closed; no mutation)"
-                ],
-                "blocker_kind": "pr_not_merged",
-            }
-        closed_prs = [pr_live]
-        # Exact mode still needs open heads for remote-delete safety gates.
-        open_prs = api_get_all(f"{base}/pulls?state=open", auth)
-    else:
-        # Preserve historical call order (closed then open) for batch callers/tests.
-        closed_prs = api_get_all(f"{base}/pulls?state=closed", auth, limit=limit)
-        open_prs = api_get_all(f"{base}/pulls?state=open", auth)
+    closed_prs = api_get_all(f"{base}/pulls?state=closed", auth, limit=limit)
+    open_prs = api_get_all(f"{base}/pulls?state=open", auth)

    merged_closed: list[dict] = []
    remote_branch_exists: dict[str, bool] = {}
@@ -11664,13 +11350,6 @@ def gitea_reconcile_merged_cleanups(
    scratch_candidates = merged_cleanup_reconcile.discover_reviewer_scratch_worktrees(
        _canonical_local_git_root()
    )
-    # #855: exact-target never inventories or mutates foreign PR scratch trees.
-    if exact_pr is not None:
-        scratch_candidates = [
-            s
-            for s in scratch_candidates
-            if int(s.get("pr_number") or 0) == int(exact_pr)
-        ]
    active_reviewer_leases: dict[int, bool] = {}
    pr_states: dict[int, dict] = {}
    for scratch in scratch_candidates:
@@ -11705,33 +11384,6 @@ def gitea_reconcile_merged_cleanups(
        active_reviewer_leases=active_reviewer_leases,
        pr_states=pr_states,
    )
-    report["selection_mode"] = selection_mode
-    if exact_pr is not None:
-        report["selected_pr_number"] = exact_pr
-        # Fail closed if exact pin somehow produced other or zero entries.
-        entries = list(report.get("entries") or [])
-        entry_numbers = []
-        for entry in entries:
-            try:
-                entry_numbers.append(int(entry.get("pr_number")))
-            except (TypeError, ValueError):
-                entry_numbers.append(entry.get("pr_number"))
-        if entry_numbers != [exact_pr]:
-            return {
-                "success": False,
-                "performed": False,
-                "executed": False,
-                "dry_run": bool(dry_run),
-                "selection_mode": selection_mode,
-                "selected_pr_number": exact_pr,
-                "reasons": [
-                    f"exact PR #{exact_pr} selection produced unexpected "
-                    f"candidate set {entry_numbers!r} "
-                    "(fail closed; no mutation)"
-                ],
-                "blocker_kind": "exact_selection_mismatch",
-                "entries": entries,
-            }

    if dry_run:
        report["dry_run"] = True
@@ -12128,7 +11780,6 @@ def gitea_audit_worktree_cleanup(
    org: str | None = None,
    repo: str | None = None,
    ttl_hours: float = worktree_cleanup_audit.DEFAULT_TTL_HOURS,
-    merged_pr_limit: int = 200,
 ) -> dict:
    """Read-only: classify every session-owned worktree under ``branches/`` (#401).

@@ -12139,26 +11790,17 @@ def gitea_audit_worktree_cleanup(
    the active issue-lock branch is read from the local lock file and treated
    as active work. Deletes nothing and mutates no Gitea state.

-    Merged PRs are fetched as well, so an issue worktree can be linked to the
-    PR that owns its branch (#858). Such a worktree only becomes removable
-    when that owning PR is unambiguous and merged, the worktree head is
-    already contained in authoritative master, and nothing else protects it —
-    no open or competing PR, lease, issue lock, live session, dirty file, or
-    protected/control checkout. Anything unproven keeps it classified as
-    active issue work.
-
-    Fails closed if the live open-PR list, the merged-PR list, or the
-    control-plane lease state cannot be read: without them removability
-    cannot be proven, so no candidates are returned.
+    Fails closed if the live open-PR list cannot be fetched: without it,
+    removability cannot be proven, so no candidates are returned.

    Args:
        remote: Known instance — 'dadeschools' or 'prgs'.
        host: Override the Gitea host.
        org: Override the owner/organization.
        repo: Override the repository name.
-        ttl_hours: Age (hours) after which a clean conflict-fix worktree
-            becomes stale-removable (default from GITEA_WORKTREE_TTL_HOURS).
-        merged_pr_limit: Max closed PRs scanned for merged-PR ownership.
+        ttl_hours: Age (hours) after which a clean issue/conflict-fix
+            worktree becomes stale-removable (default from
+            GITEA_WORKTREE_TTL_HOURS).

    Returns:
        dict with per-worktree classifications, counts, removable
@@ -12194,84 +11836,22 @@ def gitea_audit_worktree_cleanup(
        if (pr.get("head") or {}).get("ref")
    }

-    # #858: merged PRs are the ownership evidence that lets a landed issue
-    # worktree stop being reported as active work. Without them the audit can
-    # never agree with the PR-scoped reconciler, so treat a fetch failure the
-    # same way an open-PR fetch failure is treated: fail closed.
-    try:
-        closed_prs = api_get_all(
-            f"{repo_api_url(h, o, r)}/pulls?state=closed", auth, limit=merged_pr_limit
-        )
-    except Exception as exc:
-        return {
-            "success": False,
-            "performed": False,
-            "open_pr_state_verified": True,
-            "merged_pr_state_verified": False,
-            "reasons": [
-                "could not fetch merged PRs; worktree ownership unverified "
-                f"(fail closed): {_redact(str(exc))}"
-            ],
-        }
-    merged_prs = [pr for pr in closed_prs if (pr.get("merged") or pr.get("merged_at"))]
-    pr_index = worktree_cleanup_audit.build_pr_index(list(open_prs) + merged_prs)
-
-    # #858: the auditor already accepted lease evidence but nothing ever
-    # supplied it, so every worktree looked unleased. Removability is now
-    # reachable for issue worktrees, so authoritative control-plane leases
-    # must be readable or the audit fails closed.
-    db, lease_errs = _control_plane_db_or_error()
-    if db is None:
-        return {
-            "success": False,
-            "performed": False,
-            "open_pr_state_verified": True,
-            "merged_pr_state_verified": True,
-            "lease_state_verified": False,
-            "reasons": [
-                "could not read control-plane leases; worktree protection "
-                "unverified (fail closed)",
-                *lease_errs,
-            ],
-        }
-    lease_result = lease_lifecycle.list_active_leases(
-        db, remote=remote, org=o, repo=r, include_non_active=False, limit=500
-    )
-    leased_issue_numbers: set[int] = set()
-    live_session_paths: set[str] = set()
-    for lease in lease_result.get("leases") or []:
-        if lease.get("work_kind") == "issue" and lease.get("work_number") is not None:
-            try:
-                leased_issue_numbers.add(int(lease["work_number"]))
-            except (TypeError, ValueError):
-                pass
-        if lease.get("worktree_path"):
-            live_session_paths.add(str(lease["worktree_path"]))
-
    active_issue_branches: set[str] = set()
    lock = merged_cleanup_reconcile.read_issue_lock(ISSUE_LOCK_FILE)
    if lock and lock.get("branch_name"):
        active_issue_branches.add(str(lock["branch_name"]).strip())

-    master_ref = f"{remote}/master" if remote in REMOTES else "origin/master"
    report = worktree_cleanup_audit.audit_branches_directory(
        _canonical_local_git_root(),
        open_pr_branches=open_pr_branches,
        active_issue_branches=active_issue_branches,
        now=datetime.now(timezone.utc),
        ttl_hours=ttl_hours,
-        pr_index=pr_index,
-        leased_issue_numbers=leased_issue_numbers,
-        live_session_paths=live_session_paths,
-        master_ref=master_ref,
    )
    return {
        "success": True,
        "performed": False,
        "open_pr_state_verified": True,
-        "merged_pr_state_verified": True,
-        "lease_state_verified": True,
-        "master_ref": master_ref,
        "task_mode": "work-issue",
        **report,
    }
@@ -19106,59 +18686,10 @@ def gitea_update_pr_branch_by_merge(
        prepared_verdict_head_sha=live_pr_head,
    )

-    # #871: the remote head is now advanced; the durable linked-issue lock must
-    # be advanced with it, or a later dead-session recovery can never prove
-    # ownership at the new head. This runs AFTER the successful remote update, so
-    # a failure here is a *partial* lifecycle failure — the remote moved but the
-    # durable state did not — and must never be reported as a full success.
-    claimant = _work_lease_claimant(h)
-    matched_issue = ownership.get("matched_issue")
-    synced_at = datetime.now(timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ")
-    lock_refresh: dict = {
-        "refreshed": False,
-        "reasons": ["durable lock head refresh was not attempted"],
-    }
-    if new_head and matched_issue and source_branch and (wt or None):
-        try:
-            lock_refresh = issue_lock_store.apply_durable_lock_head_refresh(
-                remote=remote,
-                org=o,
-                repo=r,
-                issue_number=int(matched_issue),
-                branch_name=source_branch,
-                worktree_path=wt,
-                pr_number=pr_number,
-                identity=claimant.get("username"),
-                profile=claimant.get("profile"),
-                current_pid=os.getpid(),
-                expected_old_head=live_pr_head,
-                new_head=new_head,
-                synced_at=synced_at,
-                base_head=live_base_head,
-            )
-        except Exception as exc:
-            lock_refresh = {
-                "refreshed": False,
-                "reasons": [
-                    f"durable lock head refresh raised (fail closed): {_redact(str(exc))}"
-                ],
-            }
-    else:
-        lock_refresh = {
-            "refreshed": False,
-            "reasons": [
-                "durable lock head refresh could not run: missing new head, "
-                "linked issue, source branch, or worktree binding"
-            ],
-        }
-
-    durable_refreshed = bool(lock_refresh.get("refreshed"))
-    base_result = {
+    return {
+        "success": True,
        "performed": True,
        "mutation_allowed": True,
-        "durable_lock_refreshed": durable_refreshed,
-        "durable_lock_refresh": lock_refresh,
-        "fully_synchronized": durable_refreshed,
        "style": "merge",
        "force_push": False,
        "rebase": False,
@@ -19180,37 +18711,19 @@ def gitea_update_pr_branch_by_merge(
        "prepared_verdict_invalidated": transition.get(
            "prepared_verdict_invalidated"
        ),
+        "recommended_next_action": transition.get(
+            "recommended_next_action",
+            pr_sync_status.ACTION_FRESH_REVIEW_REQUIRED,
+        ),
        "transition": transition,
        "role_kind": role,
        "profile_name": profile.get("profile_name"),
        "worktree_path": wt or None,
+        "reasons": list(transition.get("reasons") or []) + [
+            "update-by-merge completed via native Gitea API (style=merge only)"
+        ],
    }

-    if durable_refreshed:
-        base_result["success"] = True
-        base_result["recommended_next_action"] = transition.get(
-            "recommended_next_action",
-            pr_sync_status.ACTION_FRESH_REVIEW_REQUIRED,
-        )
-        base_result["reasons"] = list(transition.get("reasons") or []) + [
-            "update-by-merge completed via native Gitea API (style=merge only)",
-            f"durable linked-issue lock #{matched_issue} head refreshed to "
-            f"{new_head} (verified by read-after-write)",
-        ]
-        return base_result
-
-    # Partial lifecycle failure: the remote advanced but the durable lock did
-    # not. Do NOT report a fully successful synchronization (#871).
-    base_result["success"] = False
-    base_result["partial_lifecycle_failure"] = True
-    base_result["recommended_next_action"] = pr_sync_status.ACTION_BLOCKED
-    base_result["reasons"] = list(lock_refresh.get("reasons") or []) + [
-        f"PARTIAL LIFECYCLE FAILURE: PR #{pr_number} remote head advanced to "
-        f"{new_head} but the durable linked-issue lock head was not refreshed; "
-        "the synchronization is NOT complete",
-    ]
-    return base_result
-

@mcp.tool()
 def gitea_assess_conflict_fix_push(
@@ -16,16 +16,11 @@ ISSUE_LOCK_FILE = os.environ.get("GITEA_ISSUE_LOCK_FILE", "/tmp/gitea_issue_lock
 SOURCE_LOCK_ISSUE = "gitea_lock_issue"
 SOURCE_LOCK_ADOPTION = "gitea_lock_issue_adoption"
 SOURCE_OPERATOR_OVERRIDE = "operator_override"
-# #864: dirty-preserving same-claimant author-session rebind (dead owner PID).
-SOURCE_DIRTY_SAME_CLAIMANT_REBIND = (
-    "gitea_rebind_dirty_same_claimant_author_session"
-)

 SANCTIONED_LOCK_SOURCES = frozenset({
    SOURCE_LOCK_ISSUE,
    SOURCE_LOCK_ADOPTION,
    SOURCE_OPERATOR_OVERRIDE,
-    SOURCE_DIRTY_SAME_CLAIMANT_REBIND,
 })

 _OPERATOR_OVERRIDE_ENV = "GITEA_ISSUE_LOCK_OPERATOR_OVERRIDE"
@@ -85,12 +85,6 @@ HEAD_RELATION_STRICT_DESCENDANT = "strict_descendant"
 # #772: an unpublished claim has no recorded head to compare against at all, so
 # its head is measured against the base the branch was cut from instead.
 HEAD_RELATION_DESCENDS_FROM_BASE = "descends_from_recorded_base"
-# #871: the remote/PR head advanced *past* the recorded head via a sanctioned
-# merge-based branch synchronization (``gitea_update_pr_branch_by_merge``) while
-# the local worktree stayed at the recorded head. This is the inverse of the
-# #768 descendant relation — here the *remote* strictly descends the local head,
-# and only because a base was merged into the branch, proven server-side.
-HEAD_RELATION_REMOTE_MERGE_SYNCED = "remote_merge_synced"

 # Which body of evidence a recovery was decided on (#772 AC10). These are not
 # interchangeable: a published claim proves ownership against a remote/PR head,
@@ -272,70 +266,6 @@ def _assess_base_descendancy(
    ]


-def _assess_remote_merge_synced(
-    sync_provenance: Mapping[str, Any] | None,
-    *,
-    recorded_head: str,
-    remote_head: str,
-) -> tuple[bool, list[str]]:
-    """Did ``remote_head`` advance past ``recorded_head`` via a sanctioned
-    merge-based branch sync (#871)?
-
-    ``sync_provenance`` is the server-side git observation from
-    ``issue_lock_worktree.read_merge_sync_provenance``. Its own
-    ``prior_head_sha`` / ``synced_head_sha`` are re-checked against the heads
-    this assessment is actually reasoning about, so an observation taken for some
-    other pair of commits — stale, mismatched, or hand-built — can never
-    authorize recovery. This is the inverse of ``_assess_strict_descendant``: the
-    recorded head is the ancestor and the *remote* head is the descendant, and it
-    is accepted only because the remote head is a base-into-branch merge that
-    preserved the branch mainline back to the recorded head.
-
-    Returns ``(proven, notes)``. Notes name the exact missing element so a
-    refused caller sees why, never a bare "unproven".
-    """
-    if not isinstance(sync_provenance, Mapping):
-        return False, [
-            "no server-derived merge-sync provenance observation was available; a "
-            "remote head ahead of the recorded head cannot be accepted"
-        ]
-
-    probe_prior = _text(sync_provenance.get("prior_head_sha"))
-    probe_synced = _text(sync_provenance.get("synced_head_sha"))
-    if probe_prior != recorded_head or probe_synced != remote_head:
-        return False, [
-            f"merge-sync observation covers {probe_prior or 'unknown'} -> "
-            f"{probe_synced or 'unknown'}, not the heads under assessment "
-            f"({recorded_head} -> {remote_head})"
-        ]
-    if not sync_provenance.get("probe_ok"):
-        return False, (
-            list(sync_provenance.get("reasons") or [])
-            or ["merge-sync provenance probe did not complete; provenance unproven"]
-        )
-    if not sync_provenance.get("prior_is_ancestor"):
-        return False, [
-            f"recorded head {recorded_head} is not an ancestor of remote head "
-            f"{remote_head}; a rewritten or force-moved head cannot be recovered"
-        ]
-    if not sync_provenance.get("is_merge_sync"):
-        return False, (
-            list(sync_provenance.get("reasons") or [])
-            or [
-                f"remote head {remote_head} is not a sanctioned merge-based sync "
-                f"of the base into the branch above {recorded_head}"
-            ]
-        )
-
-    proof = _text(sync_provenance.get("proof")) or (
-        f"{remote_head} merged the base into the branch above {recorded_head}"
-    )
-    return True, [
-        f"remote head {remote_head} advanced past recorded head {recorded_head} "
-        f"via a sanctioned merge-based branch sync ({proof})"
-    ]
-
-
 def assess_dead_session_lock_recovery(
    existing_lock: Mapping[str, Any] | None,
    *,
@@ -360,7 +290,6 @@ def assess_dead_session_lock_recovery(
    remote_branch_exists: bool | None = None,
    recorded_base_sha: str | None = None,
    base_ancestry: Mapping[str, Any] | None = None,
-    sync_provenance: Mapping[str, Any] | None = None,
 ) -> dict[str, Any]:
    """Decide whether a dead-session author lock may be natively recovered.

@@ -540,39 +469,19 @@ def assess_dead_session_lock_recovery(
                    head_relation = HEAD_RELATION_STRICT_DESCENDANT
                    ancestry_proof = notes[0] if notes else None
                else:
-                    # #871: the reverse relation — the remote head advanced past
-                    # the recorded/local head via a sanctioned merge-based branch
-                    # sync while the local worktree stayed put. Accepted only on
-                    # server-proven merge-sync provenance, never a caller claim.
-                    synced, sync_notes = _assess_remote_merge_synced(
-                        sync_provenance,
-                        recorded_head=local_head,
-                        remote_head=remote_head,
+                    reasons.append(
+                        f"local head {local_head} does not match remote branch head "
+                        f"{remote_head}"
                    )
-                    if synced:
-                        head_relation = HEAD_RELATION_REMOTE_MERGE_SYNCED
-                        ancestry_proof = sync_notes[0] if sync_notes else None
-                    else:
-                        reasons.append(
-                            f"local head {local_head} does not match remote branch "
-                            f"head {remote_head}"
-                        )
-                        reasons.extend(notes)
-                        reasons.extend(sync_notes)
+                    reasons.extend(notes)
    evidence["recorded_base"] = recorded_base or None
    evidence["local_head"] = local_head or None
    evidence["remote_head"] = remote_head or None
    # ``recorded_head`` is the head recovery is being measured against;
    # ``accepted_head`` is the head this recovery actually adopts. They differ
    # only in the descendant case, and downstream gates need both (#768 AC2/AC7).
-    # #871: in the merge-sync case the branch/PR already carries the synced
-    # remote head, so that is the head recovery adopts; the local worktree stays
-    # at the ancestor recorded head.
    evidence["recorded_head"] = remote_head or None
-    if head_relation == HEAD_RELATION_REMOTE_MERGE_SYNCED:
-        evidence["accepted_head"] = remote_head or None
-    else:
-        evidence["accepted_head"] = local_head or None
+    evidence["accepted_head"] = local_head or None
    evidence["head_relation"] = head_relation
    evidence["ancestry_proof"] = ancestry_proof

@@ -584,17 +493,12 @@ def assess_dead_session_lock_recovery(
        # contradictory; re-stating it as a head mismatch would only obscure why.
        if not unpublished and local_head and pr_head != local_head:
            # A descendant recovery has not been published yet, so the open PR
-            # legitimately still points at the recorded head. A merge-sync
-            # recovery's PR legitimately sits at the advanced remote head. Any
-            # other disagreement is a real mismatch.
+            # legitimately still points at the recorded head. Any other
+            # disagreement is a real mismatch.
            if not (
                head_relation == HEAD_RELATION_STRICT_DESCENDANT
                and remote_head
                and pr_head == remote_head
-            ) and not (
-                head_relation == HEAD_RELATION_REMOTE_MERGE_SYNCED
-                and remote_head
-                and pr_head == remote_head
            ):
                reasons.append(
                    f"open PR #{pr_number} head {pr_head} does not match local head "
@@ -715,11 +619,7 @@ def assess_dead_session_lock_recovery(
        )
    if (
        head_relation
-        in (
-            HEAD_RELATION_STRICT_DESCENDANT,
-            HEAD_RELATION_DESCENDS_FROM_BASE,
-            HEAD_RELATION_REMOTE_MERGE_SYNCED,
-        )
+        in (HEAD_RELATION_STRICT_DESCENDANT, HEAD_RELATION_DESCENDS_FROM_BASE)
        and ancestry_proof
    ):
        proof.append(ancestry_proof)
@@ -797,16 +697,6 @@ def owning_pr_recovery_evidence(
            return None
        if accepted_head != local_head:
            return None
-    elif relation == HEAD_RELATION_REMOTE_MERGE_SYNCED:
-        # #871: the PR already sits at the advanced remote head; the local
-        # worktree is the ancestor the merge preserved. The head the open PR
-        # shows and the head recovery adopts are both the synced remote head.
-        if not remote_head or pr_head != remote_head:
-            return None
-        if accepted_head != remote_head:
-            return None
-        if not local_head or local_head == remote_head:
-            return None
    else:
        return None
    try:
@@ -875,18 +765,6 @@ def recovered_owning_pr_from_lock(
            return None
        if not accepted_head or accepted_head == recorded_head:
            return None
-    elif relation == HEAD_RELATION_REMOTE_MERGE_SYNCED:
-        # #871: PR sits at the advanced remote head, which is both the recorded
-        # measured-against head and the adopted head; the local worktree is the
-        # ancestor the merge preserved.
-        remote_head = _text(record.get("remote_head"))
-        local_head = _text(record.get("local_head"))
-        if not remote_head or pr_head != remote_head:
-            return None
-        if accepted_head and accepted_head != remote_head:
-            return None
-        if not local_head or local_head == remote_head:
-            return None
    else:
        return None
    try:
@@ -15,15 +15,27 @@ import json
 import os
 import re
 import tempfile
+import uuid
 from contextlib import contextmanager
 from datetime import datetime, timedelta, timezone
 from typing import Any

+import lease_policy
+
 LOCK_DIR_ENV = "GITEA_ISSUE_LOCK_DIR"
 DEFAULT_LOCK_DIR = os.path.expanduser("~/.cache/gitea-tools/issue-locks")
-WORK_LEASE_TTL_HOURS = 4
 AUTHOR_ISSUE_WORK_LEASE = "author_issue_work"

+# Freshness classifications. ``STATUS_STALE`` remains the dead-PID band that
+# #753 recovery keys on; the two bands below are new in #790 Slice A and apply
+# only to leases minted under the heartbeat lifecycle.
+STATUS_LIVE = "live"
+STATUS_EXPIRED = "expired"
+STATUS_ABSENT = "absent"
+STATUS_STALE = "stale"
+STATUS_STALE_MISSED_HEARTBEAT = "stale_missed_heartbeat"
+STATUS_STALE_ABSOLUTE_CAP = "stale_absolute_cap"
+
 _SAFE_SEGMENT_RE = re.compile(r"[^A-Za-z0-9._+-]+")


@@ -253,6 +265,331 @@ def bind_session_lock(
    return path


+def _ownership_refusals(
+    lock: dict[str, Any],
+    *,
+    issue_number: int,
+    branch_name: str,
+    worktree_path: str,
+    identity: str | None,
+    profile: str | None,
+) -> list[str]:
+    """Exact-ownership mismatches between a durable lock and a live caller.
+
+    Shared by the heartbeat writer and the legacy rebind path so the two cannot
+    disagree about what "the same owner" means. Every field is compared against
+    durable state; nothing is taken on the caller's word beyond the identity the
+    server itself resolved.
+    """
+    reasons: list[str] = []
+    if lock.get("issue_number") != issue_number:
+        reasons.append(
+            f"lock targets issue #{lock.get('issue_number')}, not #{issue_number}"
+        )
+    if str(lock.get("branch_name") or "") != str(branch_name or ""):
+        reasons.append(
+            f"lock branch '{lock.get('branch_name')}' does not match '{branch_name}'"
+        )
+    if not _same_realpath(str(lock.get("worktree_path") or ""), worktree_path):
+        reasons.append(
+            f"lock worktree '{lock.get('worktree_path')}' does not match "
+            f"'{worktree_path}'"
+        )
+    lease = lock.get("work_lease") if isinstance(lock, dict) else None
+    claimant = lease.get("claimant") if isinstance(lease, dict) else None
+    claimant = claimant if isinstance(claimant, dict) else {}
+    recorded_identity = str(claimant.get("username") or "").strip()
+    recorded_profile = str(claimant.get("profile") or "").strip()
+    if not recorded_identity or not recorded_profile:
+        reasons.append("lock does not record both a claimant username and profile")
+    if recorded_identity and recorded_identity != str(identity or "").strip():
+        reasons.append(
+            f"lock claimant '{recorded_identity}' does not match active identity "
+            f"'{str(identity or '').strip() or 'unknown'}'"
+        )
+    if recorded_profile and recorded_profile != str(profile or "").strip():
+        reasons.append(
+            f"lock profile '{recorded_profile}' does not match active profile "
+            f"'{str(profile or '').strip() or 'unknown'}'"
+        )
+    return reasons
+
+
+def _refusal(reasons: list[str], **extra: Any) -> dict[str, Any]:
+    return {"success": False, "performed": False, "reasons": reasons, **extra}
+
+
+def heartbeat_session_lock(
+    *,
+    remote: str,
+    org: str,
+    repo: str,
+    issue_number: int,
+    branch_name: str,
+    worktree_path: str,
+    identity: str | None,
+    profile: str | None,
+    task_session_id: str,
+    expected_generation: int | None = None,
+    lock_dir: str | None = None,
+    now: datetime | None = None,
+) -> dict[str, Any]:
+    """Slide a heartbeat-lifecycle lease forward (#790 Slice A, A4).
+
+    The write happens inside the same per-issue ``flock`` that serializes
+    acquisition, and under the #772 generation compare-and-swap, so a heartbeat
+    can never race a concurrent reclaim: whichever lands first moves the
+    generation and the other fails closed.
+
+    Refuses — never revives — in every ambiguous case. A lease that has already
+    lapsed past its grace is *not* heartbeatable: allowing that would let a
+    session that stopped proving liveness restore ownership retroactively, which
+    is precisely the revival AC-N5 forbids. Such a session must go through the
+    sanctioned reclaim path, which mints a fresh generation.
+    """
+    current = _lease_now(now)
+    root = _ensure_lock_dir(lock_dir)
+    path = lock_file_path(
+        remote=remote, org=org, repo=repo, issue_number=issue_number, lock_dir=root
+    )
+    declared_session = str(task_session_id or "").strip()
+    if not declared_session:
+        return _refusal(["no task_session_id supplied (fail closed)"])
+
+    sentinel = flock_path(path)
+    try:
+        with _exclusive_file_lock(sentinel):
+            lock = read_lock_file(path)
+            if not lock:
+                return _refusal([f"no durable lock for issue #{issue_number}"])
+
+            if is_legacy_lease(lock):
+                return _refusal(
+                    [
+                        "lock predates the heartbeat lifecycle; it must be rebound "
+                        "by its exact owner before it can be heartbeated"
+                    ],
+                    lifecycle=lease_lifecycle_version(lock),
+                    legacy_lease=True,
+                )
+
+            reasons = _ownership_refusals(
+                lock,
+                issue_number=issue_number,
+                branch_name=branch_name,
+                worktree_path=worktree_path,
+                identity=identity,
+                profile=profile,
+            )
+            recorded_session = lease_task_session_id(lock)
+            if not recorded_session:
+                reasons.append(
+                    "lock declares the heartbeat lifecycle but records no "
+                    "task_session_id (fail closed)"
+                )
+            elif recorded_session != declared_session:
+                # A superseded session holding an old identifier cannot heartbeat
+                # over the session that replaced it.
+                reasons.append(
+                    "task_session_id does not match the session recorded on the lock"
+                )
+            if reasons:
+                return _refusal(reasons)
+
+            current_generation = lock_generation(lock)
+            if (
+                expected_generation is not None
+                and current_generation != expected_generation
+            ):
+                return _refusal(
+                    [
+                        f"lock generation changed: expected {expected_generation}, "
+                        f"found {current_generation}; another session reclaimed or "
+                        "replaced this claim (fail closed)"
+                    ],
+                    lock_generation=current_generation,
+                )
+
+            freshness = assess_lock_freshness(lock, now=current)
+            if not freshness.get("live"):
+                return _refusal(
+                    [
+                        f"lease is not live ({freshness.get('status')}): "
+                        f"{freshness.get('reason')}; a lapsed lease must be "
+                        "reclaimed, not heartbeated"
+                    ],
+                    freshness=freshness,
+                )
+
+            policy = lease_policy.policy_for(lease_task_class(lock))
+            expires = current + timedelta(minutes=policy.initial_ttl_minutes)
+            record = dict(lock)
+            lease = dict(record.get("work_lease") or {})
+            prior_heartbeat = lease.get("last_heartbeat_at")
+            lease["last_heartbeat_at"] = _format_lease_timestamp(current)
+            lease["expires_at"] = _format_lease_timestamp(expires)
+            try:
+                lease["heartbeat_count"] = int(lease.get("heartbeat_count") or 0) + 1
+            except (TypeError, ValueError):
+                lease["heartbeat_count"] = 1
+            record["work_lease"] = lease
+            record["lock_generation"] = current_generation + 1
+            save_lock_file(path, record)
+    except LockContentionError as exc:
+        return _refusal([f"issue #{issue_number} lock contention: {exc} (fail closed)"])
+
+    return {
+        "success": True,
+        "performed": True,
+        "issue_number": issue_number,
+        "branch_name": branch_name,
+        "worktree_path": worktree_path,
+        "task_session_id": declared_session,
+        "lock_generation": record["lock_generation"],
+        "prior_generation": current_generation,
+        "prior_heartbeat_at": prior_heartbeat,
+        "last_heartbeat_at": lease["last_heartbeat_at"],
+        "expires_at": lease["expires_at"],
+        "heartbeat_count": lease["heartbeat_count"],
+        "lock_file_path": path,
+        "policy": lease_policy.describe(lease_task_class(record)),
+        "freshness": assess_lock_freshness(record, now=current),
+    }
+
+
+def rebind_legacy_lock(
+    *,
+    remote: str,
+    org: str,
+    repo: str,
+    issue_number: int,
+    branch_name: str,
+    worktree_path: str,
+    identity: str | None,
+    profile: str | None,
+    expected_generation: int | None = None,
+    lock_dir: str | None = None,
+    now: datetime | None = None,
+) -> dict[str, Any]:
+    """Move a legacy lock into the heartbeat lifecycle (#790 AC-N8).
+
+    One of the two sanctioned exits from the preserved-expiry legacy state; the
+    other is terminal retirement, which is Slice B. Only the exact recorded
+    owner may rebind, and only while the legacy lock is still live under its
+    original absolute expiry — an already-expired legacy lease belongs to the
+    #760 renewal path or #601 reclaim, and this must not become a second, weaker
+    way to revive one.
+
+    The rebind mints a genuine task-session identifier and a genuine first
+    heartbeat. It does not fabricate history: the original creation and expiry
+    are preserved under ``legacy_origin`` for audit, and the new lifecycle's
+    absolute cap runs from the rebind, not from the legacy claim.
+    """
+    current = _lease_now(now)
+    root = _ensure_lock_dir(lock_dir)
+    path = lock_file_path(
+        remote=remote, org=org, repo=repo, issue_number=issue_number, lock_dir=root
+    )
+    sentinel = flock_path(path)
+    try:
+        with _exclusive_file_lock(sentinel):
+            lock = read_lock_file(path)
+            if not lock:
+                return _refusal([f"no durable lock for issue #{issue_number}"])
+            if not is_legacy_lease(lock):
+                return _refusal(
+                    [
+                        "lock is already on the heartbeat lifecycle; use the "
+                        "heartbeat path"
+                    ],
+                    lifecycle=lease_lifecycle_version(lock),
+                    legacy_lease=False,
+                )
+
+            reasons = _ownership_refusals(
+                lock,
+                issue_number=issue_number,
+                branch_name=branch_name,
+                worktree_path=worktree_path,
+                identity=identity,
+                profile=profile,
+            )
+            if reasons:
+                return _refusal(reasons)
+
+            current_generation = lock_generation(lock)
+            if (
+                expected_generation is not None
+                and current_generation != expected_generation
+            ):
+                return _refusal(
+                    [
+                        f"lock generation changed: expected {expected_generation}, "
+                        f"found {current_generation} (fail closed)"
+                    ],
+                    lock_generation=current_generation,
+                )
+
+            freshness = assess_lock_freshness(lock, now=current)
+            if not freshness.get("live"):
+                return _refusal(
+                    [
+                        f"legacy lease is not live ({freshness.get('status')}): "
+                        f"{freshness.get('reason')}; rebinding is not a recovery "
+                        "path for a lapsed lease"
+                    ],
+                    freshness=freshness,
+                )
+
+            policy = lease_policy.policy_for(lease_task_class(lock))
+            expires = current + timedelta(minutes=policy.initial_ttl_minutes)
+            session_id = mint_task_session_id(lease_task_class(lock))
+            record = dict(lock)
+            lease = dict(record.get("work_lease") or {})
+            legacy_origin = {
+                "created_at": lease.get("created_at"),
+                "expires_at": lease.get("expires_at"),
+                "last_heartbeat_at": lease.get("last_heartbeat_at"),
+                "lifecycle": lease_policy.LIFECYCLE_LEGACY,
+            }
+            lease["lifecycle_version"] = lease_policy.LIFECYCLE_HEARTBEAT_V1
+            lease["task_session_id"] = session_id
+            lease["created_at"] = _format_lease_timestamp(current)
+            lease["last_heartbeat_at"] = _format_lease_timestamp(current)
+            lease["expires_at"] = _format_lease_timestamp(expires)
+            lease["heartbeat_count"] = 1
+            record["work_lease"] = lease
+            record["legacy_rebind"] = {
+                "rebound_at": _format_lease_timestamp(current),
+                "task_session_id": session_id,
+                "prior_generation": current_generation,
+                "legacy_origin": legacy_origin,
+                "reason": (
+                    "legacy lock rebound into the heartbeat lifecycle by its exact "
+                    "recorded owner"
+                ),
+            }
+            record["lock_generation"] = current_generation + 1
+            save_lock_file(path, record)
+    except LockContentionError as exc:
+        return _refusal([f"issue #{issue_number} lock contention: {exc} (fail closed)"])
+
+    return {
+        "success": True,
+        "performed": True,
+        "issue_number": issue_number,
+        "task_session_id": session_id,
+        "lock_generation": record["lock_generation"],
+        "prior_generation": current_generation,
+        "lifecycle": lease_policy.LIFECYCLE_HEARTBEAT_V1,
+        "legacy_rebind": record["legacy_rebind"],
+        "expires_at": lease["expires_at"],
+        "last_heartbeat_at": lease["last_heartbeat_at"],
+        "lock_file_path": path,
+        "freshness": assess_lock_freshness(record, now=current),
+    }
+
+
 def read_session_issue_lock(lock_dir: str | None = None) -> dict[str, Any] | None:
    root = (lock_dir or default_lock_dir()).strip()
    pointer = read_lock_file(session_pointer_path(root))
@@ -336,6 +673,16 @@ def _parse_lease_timestamp(value: str | None) -> datetime | None:
        return None


+def _format_lease_timestamp(value: datetime) -> str:
+    """Serialize a lease timestamp in the durable ``...Z`` form already on disk."""
+    return (
+        value.astimezone(timezone.utc)
+        .replace(microsecond=0)
+        .isoformat()
+        .replace("+00:00", "Z")
+    )
+
+
 def lease_expires_at(lock: dict[str, Any] | None) -> datetime | None:
    if not lock:
        return None
@@ -356,60 +703,216 @@ def is_lease_live(lock: dict[str, Any] | None, *, now: datetime | None = None) -
    return assess_lock_freshness(lock, now=now)["live"]


+def lease_task_class(lock_data: dict[str, Any] | None) -> str:
+    """Policy task class for a durable lock; author work when unrecorded."""
+    lease = lock_data.get("work_lease") if isinstance(lock_data, dict) else None
+    if isinstance(lease, dict):
+        recorded = str(lease.get("operation_type") or "").strip()
+        if recorded:
+            return recorded
+    return AUTHOR_ISSUE_WORK_LEASE
+
+
+def lease_lifecycle_version(lock_data: dict[str, Any] | None) -> str:
+    """Read the durable lifecycle marker (#790 AC-N8).
+
+    The marker is the *only* discriminator between a heartbeat-lifecycle lease
+    and a legacy one. Timestamps are deliberately not consulted: a lock minted
+    before this lifecycle existed has ``last_heartbeat_at == created_at``
+    forever, and reading that equality as "recently heartbeated" would treat
+    every never-heartbeated legacy lock as fresh — the precise inversion AC-N8
+    forbids. A newly minted heartbeat lease also has the two equal, so the
+    equality carries no information in either direction.
+    """
+    lease = lock_data.get("work_lease") if isinstance(lock_data, dict) else None
+    if isinstance(lease, dict):
+        recorded = str(lease.get("lifecycle_version") or "").strip()
+        if recorded:
+            return recorded
+    return lease_policy.LIFECYCLE_LEGACY
+
+
+def is_legacy_lease(lock_data: dict[str, Any] | None) -> bool:
+    """True when a lock predates the shared heartbeat lifecycle."""
+    return lease_lifecycle_version(lock_data) != lease_policy.LIFECYCLE_HEARTBEAT_V1
+
+
+def lease_task_session_id(lock_data: dict[str, Any] | None) -> str:
+    """Recorded per-task session identifier, or empty for a legacy lock."""
+    lease = lock_data.get("work_lease") if isinstance(lock_data, dict) else None
+    if isinstance(lease, dict):
+        return str(lease.get("task_session_id") or "").strip()
+    return ""
+
+
+def mint_task_session_id(task_class: str = AUTHOR_ISSUE_WORK_LEASE) -> str:
+    """Mint an ownership key for one task (#790 AC-N1).
+
+    Deliberately contains no process identifier. The recorded PID belongs to the
+    long-lived MCP daemon, which outlives any individual task and is reused by
+    every task it serves, so PID digits cannot identify *which* task holds a
+    claim. The PID is still recorded alongside this value as evidence.
+    """
+    prefix = _sanitize_segment(str(task_class or AUTHOR_ISSUE_WORK_LEASE))
+    return f"{prefix}-{uuid.uuid4().hex[:16]}"
+
+
+def _lease_heartbeat_at(lock_data: dict[str, Any] | None) -> datetime | None:
+    lease = lock_data.get("work_lease") if isinstance(lock_data, dict) else None
+    heartbeat_at = None
+    if isinstance(lock_data, dict):
+        heartbeat_at = _parse_lease_timestamp(lock_data.get("last_heartbeat_at"))
+    if heartbeat_at is None and isinstance(lease, dict):
+        heartbeat_at = _parse_lease_timestamp(lease.get("last_heartbeat_at"))
+    return heartbeat_at
+
+
 def assess_lock_freshness(
    lock_data: dict[str, Any] | None,
    *,
    now: datetime | None = None,
 ) -> dict[str, Any]:
-    """Classify a lock as live, expired, stale, or absent."""
+    """Classify a lock as live, expired, stale, or absent.
+
+    #790 Slice A makes the heartbeat load-bearing. Before this change
+    ``last_heartbeat_at`` was parsed and then never consulted: liveness was
+    decided entirely by the absolute ``expires_at`` and by PID liveness, and
+    since the recorded PID is the long-lived MCP daemon, an abandoned author
+    task stayed "live" for the full four-hour TTL.
+
+    Two rules govern the rewrite:
+
+    * **An alive PID never establishes freshness** (AC-N2). It proves the daemon
+      is up, nothing about the task. It is recorded as evidence and no branch
+      returns ``live`` because of it.
+    * **A dead PID still corroborates staleness.** The dead-PID band is
+      unchanged and still precedes every heartbeat evaluation, so #753
+      dead-session recovery keys on exactly the classification it always did.
+
+    Legacy leases (AC-N8) keep their recorded absolute expiry and are never
+    evaluated against the short heartbeat grace, so deploying this change cannot
+    make an existing claim instantly reclaimable.
+    """
    current = _lease_now(now)
    if not lock_data:
        return {
-            "status": "absent",
+            "status": STATUS_ABSENT,
            "live": False,
            "stale": False,
            "reason": "no lock record",
        }

-    expires_at = lease_expires_at(lock_data)
    lease = lock_data.get("work_lease")
-    heartbeat_at = _parse_lease_timestamp(lock_data.get("last_heartbeat_at"))
-    if heartbeat_at is None and isinstance(lease, dict):
-        heartbeat_at = _parse_lease_timestamp(lease.get("last_heartbeat_at"))
+    expires_at = lease_expires_at(lock_data)
+    heartbeat_at = _lease_heartbeat_at(lock_data)
+    created_at = (
+        _parse_lease_timestamp(lease.get("created_at"))
+        if isinstance(lease, dict)
+        else None
+    )

    pid = lock_data.get("session_pid")
    if pid is None:
        pid = lock_data.get("pid")
+    # Evidence only. Never consulted to grant liveness (AC-N2).
    pid_alive = is_process_alive(pid) if pid is not None else False

-    if expires_at and expires_at <= current:
-        return {
-            "status": "expired",
-            "live": False,
-            "stale": True,
-            "reason": f"lease expired at {expires_at.isoformat()}",
-            "pid_alive": pid_alive,
-        }
+    lifecycle = lease_lifecycle_version(lock_data)
+    legacy = lifecycle != lease_policy.LIFECYCLE_HEARTBEAT_V1
+    policy = lease_policy.policy_for(lease_task_class(lock_data))

-    if pid is not None and not pid_alive:
-        return {
-            "status": "stale",
-            "live": False,
-            "stale": True,
-            "reason": f"owner pid {pid} is not alive",
-            "pid_alive": False,
-        }
-
-    return {
-        "status": "live",
-        "live": True,
-        "stale": False,
-        "reason": "lock heartbeat and lease are fresh",
+    evidence: dict[str, Any] = {
        "pid_alive": pid_alive,
+        "lifecycle": lifecycle,
+        "legacy_lease": legacy,
+        "task_session_id": lease_task_session_id(lock_data) or None,
        "heartbeat_at": heartbeat_at.isoformat() if heartbeat_at else None,
        "expires_at": expires_at.isoformat() if expires_at else None,
    }

+    def _result(status: str, *, live: bool, reason: str, **extra: Any) -> dict[str, Any]:
+        return {
+            "status": status,
+            "live": live,
+            "stale": not live and status != STATUS_ABSENT,
+            "reason": reason,
+            **evidence,
+            **extra,
+        }
+
+    if legacy:
+        # AC-N8: the preserved absolute expiry is the only clock for a lock
+        # written before task-session heartbeats existed.
+        if expires_at and expires_at <= current:
+            return _result(
+                STATUS_EXPIRED,
+                live=False,
+                reason=f"lease expired at {expires_at.isoformat()}",
+            )
+        if pid is not None and not pid_alive:
+            return _result(
+                STATUS_STALE, live=False, reason=f"owner pid {pid} is not alive"
+            )
+        return _result(
+            STATUS_LIVE,
+            live=True,
+            reason=(
+                "legacy lease is within its recorded absolute expiry; the "
+                "heartbeat grace does not apply retroactively"
+            ),
+            legacy_expiry_preserved=True,
+        )
+
+    # ── Heartbeat lifecycle ──
+    if pid is not None and not pid_alive:
+        # Unchanged dead-PID band: #753 recovery depends on this exact status.
+        return _result(STATUS_STALE, live=False, reason=f"owner pid {pid} is not alive")
+
+    if heartbeat_at is None:
+        # Contradictory: a heartbeat lease must carry a heartbeat. Fail closed.
+        return _result(
+            STATUS_STALE_MISSED_HEARTBEAT,
+            live=False,
+            reason=(
+                f"lease declares lifecycle '{lifecycle}' but records no "
+                "last_heartbeat_at (fail closed)"
+            ),
+        )
+
+    if policy.absolute_cap_hours and created_at is not None:
+        cap_at = created_at + timedelta(hours=policy.absolute_cap_hours)
+        if cap_at <= current:
+            return _result(
+                STATUS_STALE_ABSOLUTE_CAP,
+                live=False,
+                reason=(
+                    f"lease exceeded its {policy.absolute_cap_hours}h absolute cap "
+                    f"at {cap_at.isoformat()}; canonical re-adoption is required"
+                ),
+                absolute_cap_at=cap_at.isoformat(),
+            )
+
+    grace_at = heartbeat_at + timedelta(minutes=policy.missed_heartbeat_grace_minutes)
+    if grace_at <= current or (expires_at is not None and expires_at <= current):
+        return _result(
+            STATUS_STALE_MISSED_HEARTBEAT,
+            live=False,
+            reason=(
+                f"no valid heartbeat since {heartbeat_at.isoformat()}; the "
+                f"{policy.missed_heartbeat_grace_minutes}min grace lapsed at "
+                f"{grace_at.isoformat()}"
+            ),
+            missed_heartbeat_since=grace_at.isoformat(),
+        )
+
+    warning_at = heartbeat_at + timedelta(minutes=policy.stale_warning_minutes)
+    return _result(
+        STATUS_LIVE,
+        live=True,
+        reason="lease heartbeat is fresh within the configured grace",
+        heartbeat_warning=warning_at <= current,
+    )
+

 def _same_realpath(left: str | None, right: str | None) -> bool:
    if not left or not right:
@@ -446,6 +949,27 @@ def assess_expired_lock_reclaim(
            "reasons": ["lock is still live; cannot reclaim (fail closed)"],
            "freshness": freshness,
        }
+    status = str(freshness.get("status") or "")
+    if status in (STATUS_STALE_MISSED_HEARTBEAT, STATUS_STALE_ABSOLUTE_CAP):
+        # #790: under the heartbeat lifecycle the heartbeat *is* the liveness
+        # proof, so a session that stopped heartbeating past its grace has
+        # released its claim by definition. Requiring a dead PID on top of that
+        # would reinstate the original defect — the recorded PID is the shared
+        # daemon, which stays alive across every abandoned task it ever served.
+        #
+        # This band is unreachable for a legacy lease (AC-N8), so no lock
+        # written before this lifecycle can be reclaimed by this path.
+        return {
+            "reclaim_allowed": True,
+            "reasons": [
+                f"heartbeat-lifecycle lease is {status}: {freshness.get('reason')}"
+            ],
+            "freshness": freshness,
+            "prior_branch": existing_lock.get("branch_name"),
+            "prior_worktree": existing_lock.get("worktree_path"),
+            "prior_pid": existing_lock.get("session_pid") or existing_lock.get("pid"),
+            "prior_task_session_id": lease_task_session_id(existing_lock) or None,
+        }
    pid = existing_lock.get("session_pid")
    if pid is None:
        pid = existing_lock.get("pid")
@@ -737,308 +1261,4 @@ def format_lock_proof(
        parts.append("lock released")
    elif released is False:
        parts.append("lock retained")
-    return "; ".join(parts)
-
-
-# ── #871: durable linked-issue lock head refresh after branch synchronization ──
-_FULL_SHA_RE = re.compile(r"^[0-9a-f]{40}$", re.IGNORECASE)
-
-# Provenance recorded on the lock when the head is refreshed by a sanctioned
-# merge-based branch synchronization (``gitea_update_pr_branch_by_merge``).
-LOCK_HEAD_REFRESH_PROVENANCE_MERGE_SYNC = "gitea_update_pr_branch_by_merge"
-
-
-def _norm_sha(value: Any) -> str | None:
-    text = str(value or "").strip().lower()
-    return text if _FULL_SHA_RE.match(text) else None
-
-
-def _lock_claimant_view(lock: dict[str, Any] | None) -> dict[str, Any]:
-    if not isinstance(lock, dict):
-        return {}
-    claimant = lock.get("claimant")
-    if not isinstance(claimant, dict):
-        lease = lock.get("work_lease")
-        claimant = lease.get("claimant") if isinstance(lease, dict) else None
-    return dict(claimant) if isinstance(claimant, dict) else {}
-
-
-def assess_durable_lock_head_refresh(
-    existing_lock: dict[str, Any] | None,
-    *,
-    remote: str,
-    org: str,
-    repo: str,
-    issue_number: int,
-    branch_name: str,
-    worktree_path: str,
-    pr_number: int | None,
-    identity: str | None,
-    profile: str | None,
-    current_pid: int | None,
-    expected_old_head: str | None,
-    new_head: str | None,
-    base_head: str | None = None,
-) -> dict[str, Any]:
-    """Fail-closed assessment for refreshing a durable lock's recorded head (#871).
-
-    A successful ``gitea_update_pr_branch_by_merge`` advances the *remote* PR head
-    but must also advance the durable linked-issue lock so a later dead-session
-    recovery can prove ownership. This decides whether that refresh is permitted;
-    it mutates nothing.
-
-    Every element of durable ownership is re-verified against the persisted lock —
-    repository, issue, branch, worktree, claimant identity/profile, and the live
-    owning session — and the recorded head is compare-and-swapped: the lock's
-    currently recorded synced head (if any) must equal ``expected_old_head``, so a
-    lock whose head or provenance changed concurrently is never overwritten.
-    """
-    reasons: list[str] = []
-    old = _norm_sha(expected_old_head)
-    new = _norm_sha(new_head)
-    evidence: dict[str, Any] = {
-        "issue_number": issue_number,
-        "branch_name": branch_name,
-        "worktree_path": worktree_path,
-        "pr_number": pr_number,
-        "expected_old_head": old,
-        "new_head": new,
-        "base_head": _norm_sha(base_head),
-    }
-
-    if not isinstance(existing_lock, dict) or not existing_lock:
-        reasons.append("no durable lock exists for this issue; nothing to refresh")
-        return {"allowed": False, "reasons": reasons, "evidence": evidence,
-                "expected_generation": 0}
-
-    lock = dict(existing_lock)
-    evidence["current_generation"] = lock_generation(lock)
-
-    if lock.get("issue_number") != issue_number:
-        reasons.append(
-            f"durable lock targets issue #{lock.get('issue_number')}, not "
-            f"#{issue_number}; refusing head refresh"
-        )
-
-    for field, expected in (("remote", remote), ("org", org), ("repo", repo)):
-        actual = str(lock.get(field) or "").strip()
-        if actual != str(expected or "").strip():
-            reasons.append(
-                f"lock {field} '{actual}' does not match requested "
-                f"'{str(expected or '').strip()}'"
-            )
-
-    locked_branch = str(lock.get("branch_name") or "").strip()
-    if locked_branch != str(branch_name or "").strip():
-        reasons.append(
-            f"lock branch '{locked_branch}' does not match requested "
-            f"'{str(branch_name or '').strip()}'"
-        )
-
-    locked_worktree = str(lock.get("worktree_path") or "").strip()
-    try:
-        same_wt = bool(locked_worktree) and bool(worktree_path) and (
-            os.path.realpath(locked_worktree) == os.path.realpath(worktree_path)
-        )
-    except OSError:
-        same_wt = locked_worktree == (worktree_path or "")
-    if not same_wt:
-        reasons.append(
-            f"lock worktree '{locked_worktree}' does not match declared "
-            f"'{str(worktree_path or '').strip()}'"
-        )
-
-    claimant = _lock_claimant_view(lock)
-    locked_identity = str(claimant.get("username") or "").strip()
-    locked_profile = str(claimant.get("profile") or "").strip()
-    if not locked_identity or not locked_profile:
-        reasons.append(
-            "durable lock does not record a claimant identity/profile; "
-            "ownership could not be proven for head refresh"
-        )
-    if not str(identity or "").strip() or not str(profile or "").strip():
-        reasons.append(
-            "active session identity/profile is unknown; ownership could not be "
-            "proven for head refresh"
-        )
-    if locked_identity and str(identity or "").strip() and locked_identity != str(identity).strip():
-        reasons.append(
-            f"lock claimant '{locked_identity}' does not match active identity "
-            f"'{str(identity).strip()}'"
-        )
-    if locked_profile and str(profile or "").strip() and locked_profile != str(profile).strip():
-        reasons.append(
-            f"lock profile '{locked_profile}' does not match active profile "
-            f"'{str(profile).strip()}'"
-        )
-
-    # The refresh is written by the LIVE owning author session. A refresh is not
-    # a recovery: the current process must be the recorded owner.
-    recorded_pid = lock.get("session_pid")
-    if recorded_pid is None:
-        recorded_pid = lock.get("pid")
-    evidence["recorded_pid"] = recorded_pid
-    evidence["current_pid"] = current_pid
-    if current_pid is None:
-        reasons.append("current session pid is unknown; cannot prove live ownership")
-    else:
-        try:
-            if recorded_pid is None or int(recorded_pid) != int(current_pid):
-                reasons.append(
-                    f"durable lock is owned by pid {recorded_pid}, not the current "
-                    f"session pid {current_pid}; head refresh requires the live owner"
-                )
-        except (TypeError, ValueError):
-            reasons.append(
-                "durable lock owner pid is malformed; cannot prove live ownership"
-            )
-
-    if not old:
-        reasons.append("expected_old_head is not a full 40-char hex SHA (fail closed)")
-    if not new:
-        reasons.append("new_head is not a full 40-char hex SHA (fail closed)")
-    if old and new and old == new:
-        reasons.append(
-            "new head equals the expected old head; a sync must advance the head"
-        )
-
-    # Compare-and-swap on the recorded head: if the lock already records a synced
-    # head it must be exactly the expected old head, else another sync moved it.
-    recorded_synced = _norm_sha(lock.get("synced_pr_head"))
-    evidence["recorded_synced_pr_head"] = recorded_synced
-    if recorded_synced is not None and old is not None and recorded_synced != old:
-        reasons.append(
-            f"durable lock already records synced head {recorded_synced}, not the "
-            f"expected old head {old}; a concurrent sync changed it (CAS fail closed)"
-        )
-
-    if reasons:
-        return {"allowed": False, "reasons": reasons, "evidence": evidence,
-                "expected_generation": lock_generation(lock)}
-
-    return {
-        "allowed": True,
-        "reasons": [
-            f"durable lock for issue #{issue_number} branch '{locked_branch}' is "
-            f"owned by the live session; refresh recorded head {old} -> {new}"
-        ],
-        "evidence": evidence,
-        "expected_generation": lock_generation(lock),
-    }
-
-
-def apply_durable_lock_head_refresh(
-    *,
-    remote: str,
-    org: str,
-    repo: str,
-    issue_number: int,
-    branch_name: str,
-    worktree_path: str,
-    pr_number: int | None,
-    identity: str | None,
-    profile: str | None,
-    current_pid: int | None,
-    expected_old_head: str | None,
-    new_head: str | None,
-    synced_at: str,
-    base_head: str | None = None,
-    provenance: str = LOCK_HEAD_REFRESH_PROVENANCE_MERGE_SYNC,
-    lock_dir: str | None = None,
-) -> dict[str, Any]:
-    """CAS-refresh the durable lock's recorded head after a branch sync (#871).
-
-    Reads the durable lock from disk, re-asserts ownership via
-    ``assess_durable_lock_head_refresh``, and — only when permitted — writes the
-    new synced head through ``bind_session_lock`` with a generation compare-and-
-    swap. Then re-reads the lock and proves it records the complete new head
-    (read-after-write). Any failure at any step returns ``refreshed=False`` with
-    reasons; the caller must treat that as a partial lifecycle failure and never
-    report a fully successful synchronization.
-    """
-    existing = load_issue_lock(
-        remote=remote, org=org, repo=repo, issue_number=issue_number, lock_dir=lock_dir
-    )
-    assessment = assess_durable_lock_head_refresh(
-        existing,
-        remote=remote,
-        org=org,
-        repo=repo,
-        issue_number=issue_number,
-        branch_name=branch_name,
-        worktree_path=worktree_path,
-        pr_number=pr_number,
-        identity=identity,
-        profile=profile,
-        current_pid=current_pid,
-        expected_old_head=expected_old_head,
-        new_head=new_head,
-        base_head=base_head,
-    )
-    result: dict[str, Any] = {
-        "refreshed": False,
-        "read_after_write_ok": False,
-        "prior_head": _norm_sha(expected_old_head),
-        "new_head": _norm_sha(new_head),
-        "reasons": list(assessment.get("reasons") or []),
-        "evidence": assessment.get("evidence"),
-    }
-    if not assessment.get("allowed"):
-        return result
-
-    new = _norm_sha(new_head)
-    old = _norm_sha(expected_old_head)
-    record = dict(existing or {})
-    sync_block = {
-        "last_synced_pr_head": new,
-        "prior_pr_head": old,
-        "base_head": _norm_sha(base_head),
-        "pr_number": pr_number,
-        "provenance": provenance,
-        "synced_at": synced_at,
-        "synced_by_pid": current_pid,
-        "synced_by": {
-            "username": str(identity or "").strip() or None,
-            "profile": str(profile or "").strip() or None,
-        },
-    }
-    record["synced_pr_head"] = new
-    record["branch_sync"] = sync_block
-    history = record.get("branch_sync_history")
-    if not isinstance(history, list):
-        history = []
-    history = list(history)
-    history.append(sync_block)
-    record["branch_sync_history"] = history
-
-    try:
-        bind_session_lock(
-            record,
-            lock_dir=lock_dir,
-            expected_generation=assessment.get("expected_generation"),
-            renewal_sanctioned=True,
-        )
-    except Exception as exc:  # CAS miss or write failure — partial lifecycle failure
-        result["reasons"].append(
-            f"durable lock head refresh write failed (fail closed): {exc}"
-        )
-        return result
-
-    after = load_issue_lock(
-        remote=remote, org=org, repo=repo, issue_number=issue_number, lock_dir=lock_dir
-    )
-    after_head = _norm_sha((after or {}).get("synced_pr_head"))
-    result["lock_generation_after"] = lock_generation(after)
-    if after_head == new and new is not None:
-        result["refreshed"] = True
-        result["read_after_write_ok"] = True
-        result["reasons"].append(
-            f"durable lock recorded head refreshed to {new} and verified by "
-            "read-after-write"
-        )
-    else:
-        result["reasons"].append(
-            "read-after-write verification failed: durable lock does not record "
-            f"the new head {new} (found {after_head}); partial lifecycle failure"
-        )
-    return result
+    return "; ".join(parts)
@@ -145,175 +145,6 @@ def read_head_ancestry(
    return result


-def read_merge_sync_provenance(
-    worktree_path: str,
-    *,
-    prior_head_sha: str | None,
-    synced_head_sha: str | None,
-) -> dict:
-    """Observe whether ``synced_head_sha`` is a sanctioned merge-based branch sync
-    that advanced the PR branch past ``prior_head_sha`` (#871).
-
-    ``gitea_update_pr_branch_by_merge`` advances a PR branch by merging the base
-    branch *into* the branch (``POST /pulls/{n}/update?style=merge``). The result
-    is a merge commit ``M`` on the branch whose **first** parent is the prior
-    branch head and whose second parent is the base tip. When the owning session
-    then dies without the durable lock's recorded head being refreshed, the local
-    worktree still sits at ``prior_head_sha`` while the live PR head is ``M``.
-
-    Recovering that drift safely requires proving the remote head is *exactly*
-    such a merge-sync — not a rewrite, rebase, force-push, or an unrelated
-    commit. This is that server-side observation. It reports facts only; the
-    disposition lives in ``issue_lock_recovery``. Every field is read from git in
-    the declared worktree — nothing is supplied by, or reachable from, an MCP
-    caller (#871).
-
-    Provenance is proven only when ALL hold:
-
-    * both commits are present (a rewritten/force-moved prior head leaves the
-      object graph and fails closed);
-    * ``prior_head_sha`` is a strict ancestor of ``synced_head_sha`` (the branch
-      history is preserved, never replaced);
-    * ``synced_head_sha`` is a merge commit (two or more parents), i.e. a base
-      merged in — a plain fast-forward of new direct commits is not a sync;
-    * ``prior_head_sha`` is an ancestor of the merge's **first** parent, so the
-      branch mainline (first-parent lineage) still reaches the prior head — a
-      rebase/force-push that re-authored the branch side fails this.
-    """
-    path = (worktree_path or "").strip()
-    prior = (prior_head_sha or "").strip()
-    synced = (synced_head_sha or "").strip()
-    result: dict = {
-        "prior_head_sha": prior or None,
-        "synced_head_sha": synced or None,
-        "probe_ok": False,
-        "prior_present": False,
-        "synced_present": False,
-        "prior_is_ancestor": False,
-        "synced_is_merge": False,
-        "first_parent_reaches_prior": False,
-        "is_merge_sync": False,
-        "first_parent_sha": None,
-        "parent_count": None,
-        "proof": None,
-        "reasons": [],
-    }
-    if not path or not prior or not synced:
-        result["reasons"].append(
-            "merge-sync provenance probe requires a worktree path and both "
-            "commit SHAs"
-        )
-        return result
-    if prior == synced:
-        result["reasons"].append(
-            "prior and synced heads are identical; no branch sync occurred"
-        )
-        return result
-
-    def _present(sha: str) -> bool:
-        res = subprocess.run(
-            ["git", "-C", path, "rev-parse", "--verify", "--quiet", f"{sha}^{{commit}}"],
-            capture_output=True,
-            text=True,
-            check=False,
-        )
-        return res.returncode == 0
-
-    def _is_ancestor(ancestor: str, descendant: str) -> bool | None:
-        res = subprocess.run(
-            ["git", "-C", path, "merge-base", "--is-ancestor", ancestor, descendant],
-            capture_output=True,
-            text=True,
-            check=False,
-        )
-        if res.returncode == 0:
-            return True
-        if res.returncode == 1:
-            return False
-        return None  # failed probe — never a silent "no"
-
-    try:
-        result["prior_present"] = _present(prior)
-        result["synced_present"] = _present(synced)
-    except OSError as exc:  # git unavailable — fail closed, never assume
-        result["reasons"].append(f"merge-sync provenance probe could not run: {exc}")
-        return result
-
-    if not result["prior_present"]:
-        result["reasons"].append(
-            f"prior head {prior} is not reachable in '{path}'; history may have "
-            "been rewritten or force-moved"
-        )
-    if not result["synced_present"]:
-        result["reasons"].append(
-            f"synced head {synced} is not reachable in '{path}'"
-        )
-    if not (result["prior_present"] and result["synced_present"]):
-        return result
-
-    ancestor = _is_ancestor(prior, synced)
-    if ancestor is None:
-        result["reasons"].append(
-            "ancestry probe failed; merge-sync provenance unproven"
-        )
-        return result
-    result["prior_is_ancestor"] = bool(ancestor)
-    if not ancestor:
-        result["reasons"].append(
-            f"prior head {prior} is not an ancestor of synced head {synced}; "
-            "the branch history was not preserved (not a merge-based sync)"
-        )
-        return result
-
-    parents_res = subprocess.run(
-        ["git", "-C", path, "rev-list", "--parents", "-n", "1", synced],
-        capture_output=True,
-        text=True,
-        check=False,
-    )
-    if parents_res.returncode != 0:
-        result["reasons"].append(
-            f"could not read parents of {synced}; merge-sync provenance unproven"
-        )
-        return result
-    tokens = (parents_res.stdout or "").split()
-    # tokens[0] is the commit itself; the rest are its parents.
-    parents = tokens[1:]
-    result["parent_count"] = len(parents)
-    result["synced_is_merge"] = len(parents) >= 2
-    if not result["synced_is_merge"]:
-        result["probe_ok"] = True
-        result["reasons"].append(
-            f"synced head {synced} has {len(parents)} parent(s); a merge-based "
-            "branch sync produces a merge commit (two or more parents)"
-        )
-        return result
-    first_parent = parents[0]
-    result["first_parent_sha"] = first_parent
-
-    fp_reaches = _is_ancestor(prior, first_parent) if prior != first_parent else True
-    if fp_reaches is None:
-        result["reasons"].append(
-            "first-parent ancestry probe failed; merge-sync provenance unproven"
-        )
-        return result
-    result["first_parent_reaches_prior"] = bool(fp_reaches)
-    result["probe_ok"] = True
-    if not fp_reaches:
-        result["reasons"].append(
-            f"merge first parent {first_parent} does not reach prior head "
-            f"{prior}; the branch mainline was re-authored (not a sanctioned sync)"
-        )
-        return result
-
-    result["is_merge_sync"] = True
-    result["proof"] = (
-        f"synced head {synced} is a merge commit (parents={len(parents)}) whose "
-        f"first-parent lineage reaches prior head {prior}; base merged into branch"
-    )
-    return result
-
-
 def read_recorded_base(
    worktree_path: str,
    *,
@@ -0,0 +1,212 @@
+"""Central lease policy configuration (#790 Slice A, AC-N7).
+
+The single authoritative source for every lease duration in the project. Before
+this module the numbers were scattered: a four-hour author TTL was declared
+twice (``issue_lock_store`` and ``gitea_mcp_server``), the reviewer/merger
+sliding window lived in ``reviewer_pr_lease``, the conflict-fix window in
+``pr_work_lease``, and the control-plane default in ``control_plane_db``.
+Nothing tied them together, so tuning one class silently diverged from the
+others and no reader could answer "how long does a lease live?" without
+grepping four files.
+
+AC-N7 requires that this configuration exist *before* the first heartbeat and
+TTL behavior that reads from it, so it ships in Slice A rather than trailing the
+code it governs.
+
+Deliberate boundaries:
+
+* **Declaration is not rewiring.** Every task class is declared here, but only
+  those with ``heartbeat_lifecycle_active`` were migrated onto the shared
+  heartbeat lifecycle in Slice A — currently ``author_issue_work`` alone.
+  Reviewer, merger, and conflict-fix leases keep their own existing behavior
+  until Slice C moves them; their numbers are recorded here so the two cannot
+  drift apart unnoticed, and ``tests/test_issue_790_lease_policy.py`` asserts
+  the recorded values still equal the constants those modules use.
+* **No policy decision lives here.** This module answers "how long", never "may
+  this session proceed". Freshness, reclaim, and renewal dispositions stay in
+  ``issue_lock_store``.
+"""
+
+from __future__ import annotations
+
+import os
+from dataclasses import dataclass
+from typing import Any
+
+# Task classes. Only the first is migrated onto the shared lifecycle in Slice A.
+TASK_CLASS_AUTHOR_ISSUE_WORK = "author_issue_work"
+TASK_CLASS_REVIEWER_PR = "reviewer_pr"
+TASK_CLASS_MERGER_PR = "merger_pr"
+TASK_CLASS_CONFLICT_FIX = "conflict_fix"
+
+# Durable marker for a lease minted under the shared heartbeat lifecycle.
+#
+# #790 AC-N8: this explicit marker — never a timestamp comparison — is what
+# distinguishes a heartbeat-lifecycle lease from a legacy one. A lock written
+# before this lifecycle existed carries no marker and reads as
+# ``LIFECYCLE_LEGACY``.
+LIFECYCLE_HEARTBEAT_V1 = "heartbeat-v1"
+LIFECYCLE_LEGACY = "legacy"
+
+_ENV_PREFIX = "GITEA_LEASE_POLICY"
+
+
+@dataclass(frozen=True)
+class LeasePolicy:
+    """Durations governing one task class.
+
+    All intervals are minutes except ``absolute_cap_hours``. ``None`` for the
+    cap means the class has no maximum continuous duration.
+    """
+
+    task_class: str
+    initial_ttl_minutes: float
+    heartbeat_cadence_minutes: float
+    stale_warning_minutes: float
+    missed_heartbeat_grace_minutes: float
+    absolute_cap_hours: float | None
+    recovery_grace_minutes: float
+    terminal_race_drain_minutes: float
+    terminal_retirement_eligible: bool
+    heartbeat_lifecycle_active: bool
+
+
+# Defaults. ``author_issue_work`` adopts the reviewer window proven by #747
+# rather than inventing new numbers: a lease expires 10 minutes after its last
+# valid heartbeat, warns at half that, and an actively heartbeating session is
+# never evicted. The prior value was a fixed four hours (240 minutes) that no
+# heartbeat could shorten — the defect this issue exists to correct.
+_DEFAULTS: dict[str, LeasePolicy] = {
+    TASK_CLASS_AUTHOR_ISSUE_WORK: LeasePolicy(
+        task_class=TASK_CLASS_AUTHOR_ISSUE_WORK,
+        initial_ttl_minutes=10.0,
+        heartbeat_cadence_minutes=2.0,
+        stale_warning_minutes=5.0,
+        missed_heartbeat_grace_minutes=10.0,
+        absolute_cap_hours=8.0,
+        recovery_grace_minutes=10.0,
+        terminal_race_drain_minutes=2.0,
+        terminal_retirement_eligible=True,
+        heartbeat_lifecycle_active=True,
+    ),
+    # Declared, not rewired. These mirror reviewer_pr_lease.LEASE_TTL_MINUTES
+    # and STALE_WARNING_MINUTES; Slice C migrates the call sites.
+    TASK_CLASS_REVIEWER_PR: LeasePolicy(
+        task_class=TASK_CLASS_REVIEWER_PR,
+        initial_ttl_minutes=10.0,
+        heartbeat_cadence_minutes=2.0,
+        stale_warning_minutes=5.0,
+        missed_heartbeat_grace_minutes=10.0,
+        absolute_cap_hours=None,
+        recovery_grace_minutes=10.0,
+        terminal_race_drain_minutes=2.0,
+        terminal_retirement_eligible=False,
+        heartbeat_lifecycle_active=False,
+    ),
+    TASK_CLASS_MERGER_PR: LeasePolicy(
+        task_class=TASK_CLASS_MERGER_PR,
+        initial_ttl_minutes=10.0,
+        heartbeat_cadence_minutes=2.0,
+        stale_warning_minutes=5.0,
+        missed_heartbeat_grace_minutes=10.0,
+        absolute_cap_hours=None,
+        recovery_grace_minutes=10.0,
+        terminal_race_drain_minutes=2.0,
+        terminal_retirement_eligible=False,
+        heartbeat_lifecycle_active=False,
+    ),
+    # Mirrors pr_work_lease.DEFAULT_CONFLICT_FIX_TTL_MINUTES. Deliberately left
+    # at its current window; shortening it is Slice C's call, not this slice's.
+    TASK_CLASS_CONFLICT_FIX: LeasePolicy(
+        task_class=TASK_CLASS_CONFLICT_FIX,
+        initial_ttl_minutes=120.0,
+        heartbeat_cadence_minutes=2.0,
+        stale_warning_minutes=5.0,
+        missed_heartbeat_grace_minutes=10.0,
+        absolute_cap_hours=None,
+        recovery_grace_minutes=10.0,
+        terminal_race_drain_minutes=2.0,
+        terminal_retirement_eligible=False,
+        heartbeat_lifecycle_active=False,
+    ),
+}
+
+_NUMERIC_FIELDS = (
+    "initial_ttl_minutes",
+    "heartbeat_cadence_minutes",
+    "stale_warning_minutes",
+    "missed_heartbeat_grace_minutes",
+    "absolute_cap_hours",
+    "recovery_grace_minutes",
+    "terminal_race_drain_minutes",
+)
+
+
+def env_var_name(task_class: str, field: str) -> str:
+    """Environment variable that overrides one field of one task class."""
+    return f"{_ENV_PREFIX}_{task_class.upper()}_{field.upper()}"
+
+
+def _override(task_class: str, field: str, default: float | None) -> float | None:
+    """Read one override, falling back to *default* on anything unusable.
+
+    A malformed or non-positive override is ignored rather than raised: a typo
+    in an environment variable must not be able to mint a zero-length lease that
+    makes every claim instantly reclaimable, nor crash the server at import.
+    """
+    raw = (os.environ.get(env_var_name(task_class, field)) or "").strip()
+    if not raw:
+        return default
+    try:
+        value = float(raw)
+    except (TypeError, ValueError):
+        return default
+    if value <= 0:
+        return default
+    return value
+
+
+def policy_for(task_class: str) -> LeasePolicy:
+    """Return the effective policy for *task_class*.
+
+    Unknown task classes fall back to the author policy, which is the most
+    conservative migrated class, rather than raising — a new caller must never
+    be able to crash a lock write by naming a class this table has not learned.
+    """
+    key = str(task_class or "").strip() or TASK_CLASS_AUTHOR_ISSUE_WORK
+    base = _DEFAULTS.get(key) or _DEFAULTS[TASK_CLASS_AUTHOR_ISSUE_WORK]
+    resolved = {
+        field: _override(base.task_class, field, getattr(base, field))
+        for field in _NUMERIC_FIELDS
+    }
+    if all(resolved[field] == getattr(base, field) for field in _NUMERIC_FIELDS):
+        return base
+    return LeasePolicy(
+        task_class=base.task_class,
+        terminal_retirement_eligible=base.terminal_retirement_eligible,
+        heartbeat_lifecycle_active=base.heartbeat_lifecycle_active,
+        **resolved,
+    )
+
+
+def known_task_classes() -> tuple[str, ...]:
+    """Every declared task class, migrated or not."""
+    return tuple(_DEFAULTS)
+
+
+def describe(task_class: str) -> dict[str, Any]:
+    """Serializable view of a policy, for audit records and tool payloads."""
+    policy = policy_for(task_class)
+    return {
+        "task_class": policy.task_class,
+        "initial_ttl_minutes": policy.initial_ttl_minutes,
+        "heartbeat_cadence_minutes": policy.heartbeat_cadence_minutes,
+        "stale_warning_minutes": policy.stale_warning_minutes,
+        "missed_heartbeat_grace_minutes": policy.missed_heartbeat_grace_minutes,
+        "absolute_cap_hours": policy.absolute_cap_hours,
+        "recovery_grace_minutes": policy.recovery_grace_minutes,
+        "terminal_race_drain_minutes": policy.terminal_race_drain_minutes,
+        "terminal_retirement_eligible": policy.terminal_retirement_eligible,
+        "heartbeat_lifecycle_active": policy.heartbeat_lifecycle_active,
+        "lifecycle_version": LIFECYCLE_HEARTBEAT_V1,
+    }
@@ -32,14 +32,12 @@ TASK_CAPABILITY_MAP: dict[str, dict[str, str]] = {
        "permission": "gitea.issue.comment",
        "role": "author",
    },
-    # #864: dirty-preserving same-claimant author-session rebind (dead owner PID).
-    # Author MCP tool path. Reconciler execute is gated inside the tool via
-    # authorize_reconciler_execute + role_kind checks (not this map entry).
-    "rebind_dirty_same_claimant_author_session": {
-        "permission": "gitea.issue.comment",
-        "role": "author",
-    },
-    "gitea_rebind_dirty_same_claimant_author_session": {
+    # #790 Slice A: prove an owned author lease is still active. Strictly
+    # narrower than lock_issue — it can only slide a lease this exact session
+    # already owns, never acquire, take over, or revive one — so it gates on the
+    # same authority rather than introducing an operation name that every
+    # already-configured author profile would be missing.
+    "heartbeat_issue_lock": {
        "permission": "gitea.issue.comment",
        "role": "author",
    },
@@ -1639,358 +1639,6 @@ class TestSecondRemediationIntegration(unittest.TestCase):
        self.assertTrue(ownership_calls)


-class TestIssue855ExactPrSelector(unittest.TestCase):
-    """#855: exact pr_number pin for reconcile_merged_cleanups (#851 lifecycle)."""
-
-    def setUp(self):
-        self._remotes = patch.dict(
-            mcp_server.REMOTES,
-            {
-                "prgs": {
-                    "host": "gitea.example.com",
-                    "org": "Scaled-Tech-Consulting",
-                    "repo": "Gitea-Tools",
-                }
-            },
-        )
-        self._remotes.start()
-        patch("gitea_audit.audit_enabled", return_value=False).start()
-        self.mock_api = patch("mcp_server.api_request").start()
-        self.mock_all = patch("mcp_server.api_get_all", return_value=[]).start()
-        patch("mcp_server.get_auth_header", return_value=FAKE_AUTH).start()
-        patch(
-            "mcp_server.merged_cleanup_reconcile.is_head_ancestor_of_ref",
-            return_value=True,
-        ).start()
-        patch(
-            "mcp_server.get_profile",
-            return_value=dict(RECONCILER_WITH_DELETE),
-        ).start()
-        patch(
-            "mcp_server._profile_operation_gate",
-            return_value=[],
-        ).start()
-        patch(
-            "mcp_server._collect_branch_ownership_records",
-            return_value={"records": [], "inventory_error": False},
-        ).start()
-        patch(
-            "mcp_server.merged_cleanup_reconcile.discover_reviewer_scratch_worktrees",
-            return_value=[],
-        ).start()
-        patch("mcp_server.verify_preflight_purity", return_value=None).start()
-        patch(
-            "mcp_server.audit_reconciliation_mode.check_cleanup_execution_allowed",
-            return_value=(True, []),
-        ).start()
-
-    def tearDown(self):
-        patch.stopall()
-
-    def _merged_pr(self, number, branch, sha="c" * 40):
-        return {
-            "number": number,
-            "title": f"PR {number}",
-            "body": f"Closes #{number - 4}",
-            "merged": True,
-            "merged_at": "2026-07-23T12:00:00Z",
-            "merge_commit_sha": "f" * 40,
-            "state": "closed",
-            "head": {"ref": branch, "sha": sha},
-            "base": {"ref": "master"},
-        }
-
-    def test_exact_pr_848_ignores_newer_852_in_batch_queue(self):
-        """pr_number=848 selects only #848 even when #852 is newer/first."""
-        from mcp_server import gitea_reconcile_merged_cleanups
-
-        pr_848 = self._merged_pr(
-            848, "fix/issue-844-exclude-epic-containers", sha="c3f282ba" + "0" * 32
-        )
-        # Closed list would rank #852 first in batch mode; exact pin must ignore it.
-        closed_batch = [
-            self._merged_pr(852, "fix/issue-851-cleanup-worktree-before-remote-delete"),
-            pr_848,
-            self._merged_pr(849, "fix/issue-849-other"),
-            self._merged_pr(846, "fix/issue-846-other"),
-            self._merged_pr(845, "fix/issue-845-other"),
-        ]
-        batch_fetch_calls = []
-
-        def fake_api(method, url, *args, **kwargs):
-            if method == "GET" and url.rstrip("/").endswith("/pulls/848"):
-                return dict(pr_848)
-            if method == "GET" and "/pulls/" in url:
-                raise AssertionError(f"unexpected PR fetch: {url}")
-            if method == "GET" and "/branches/" in url:
-                return {"name": "present"}
-            return {}
-
-        def fake_all(url, auth, limit=None):
-            batch_fetch_calls.append((url, limit))
-            if "state=open" in url:
-                return []
-            if "state=closed" in url:
-                # Exact mode must not use the closed batch list.
-                raise AssertionError(
-                    "exact pr_number mode must not page closed PRs: " + url
-                )
-            return []
-
-        self.mock_api.side_effect = fake_api
-        self.mock_all.side_effect = fake_all
-        patch(
-            "mcp_server._remote_branch_exists",
-            return_value=True,
-        ).start()
-        patch(
-            "mcp_server.merged_cleanup_reconcile.build_reconciliation_report",
-            side_effect=lambda **kwargs: {
-                "entries": [
-                    {
-                        "pr_number": int(pr["number"]),
-                        "head_branch": (pr.get("head") or {}).get("ref"),
-                        "issue_number": 844,
-                        "remote_branch": {
-                            "safe_to_delete_remote": True,
-                            "head_branch": (pr.get("head") or {}).get("ref"),
-                        },
-                        "local_worktree": {
-                            "safe_to_remove_worktree": True,
-                            "worktree_path": (
-                                "/tmp/branches/fix-issue-844-exclude-epic-containers"
-                            ),
-                        },
-                        "planned_execution_order": (
-                            mcp_server.merged_cleanup_reconcile.plan_cleanup_execution_order(
-                                remote_assessment={"safe_to_delete_remote": True},
-                                local_assessment={"safe_to_remove_worktree": True},
-                            )
-                        ),
-                    }
-                    for pr in kwargs.get("closed_prs") or []
-                    if pr.get("merged_at") or pr.get("merged")
-                ],
-                "reviewer_scratch_entries": [],
-                "merged_pr_count": len(kwargs.get("closed_prs") or []),
-            },
-        ).start()
-
-        res = gitea_reconcile_merged_cleanups(
-            dry_run=True,
-            pr_number=848,
-            remote="prgs",
-            org="Scaled-Tech-Consulting",
-            repo="Gitea-Tools",
-        )
-        self.assertTrue(res.get("success"))
-        self.assertFalse(res.get("performed"))
-        self.assertEqual(res.get("selection_mode"), "exact_pr")
-        self.assertEqual(res.get("selected_pr_number"), 848)
-        entries = res.get("entries") or []
-        self.assertEqual(len(entries), 1, entries)
-        self.assertEqual(entries[0].get("pr_number"), 848)
-        self.assertEqual(
-            entries[0].get("head_branch"),
-            "fix/issue-844-exclude-epic-containers",
-        )
-        # No other PR appears in plan.
-        self.assertEqual(list((res.get("planned_execution_orders") or {}).keys()), ["848"])
-        plan = (res.get("planned_execution_orders") or {}).get("848") or []
-        actions = [s.get("action") for s in plan]
-        self.assertEqual(
-            actions,
-            [
-                "remove_local_worktree",
-                "reassess_branch_ownership",
-                "delete_remote_branch",
-            ],
-        )
-        # Prove we never scanned the multi-PR closed batch.
-        self.assertFalse(any("state=closed" in (u or "") for u, _ in batch_fetch_calls))
-        # closed_batch fixture must remain unused (sanity).
-        self.assertEqual(closed_batch[0]["number"], 852)
-
-    def test_exact_pr_execute_only_mutates_selected_pr(self):
-        """Execute with pr_number must never touch #845/#846/#849/#852."""
-        from mcp_server import gitea_reconcile_merged_cleanups
-
-        pr_848 = self._merged_pr(848, "fix/issue-844-exclude-epic-containers")
-        worktree_path = "/tmp/branches/fix-issue-844-exclude-epic-containers"
-        remove_calls = []
-        delete_api_calls = []
-        ownership_branches = []
-
-        def fake_api(method, url, *args, **kwargs):
-            if method == "GET" and url.rstrip("/").endswith("/pulls/848"):
-                return dict(pr_848)
-            if method == "DELETE":
-                delete_api_calls.append(url)
-                # Forbid foreign PR branch deletion by URL content.
-                for forbidden in ("845", "846", "849", "852"):
-                    self.assertNotIn(forbidden, url)
-            return {}
-
-        def fake_remove(project_root, branch, worktree_path=None):
-            remove_calls.append({"branch": branch, "worktree_path": worktree_path})
-            return {
-                "success": True,
-                "performed": True,
-                "message": f"removed {worktree_path}",
-                "worktree_path": worktree_path,
-            }
-
-        def fake_collect(**kwargs):
-            ownership_branches.append(kwargs.get("branch"))
-            return {"records": [], "inventory_error": False}
-
-        def fake_probe(h, o, r, auth, br):
-            return guard.classify_branch_readback_http_status(
-                404, not_found_scope=guard.NOT_FOUND_SCOPE_BRANCH
-            )
-
-        self.mock_api.side_effect = fake_api
-        self.mock_all.side_effect = lambda url, auth, limit=None: []
-        patch("mcp_server._remote_branch_exists", return_value=True).start()
-        patch(
-            "mcp_server.merged_cleanup_reconcile.build_reconciliation_report",
-            return_value={
-                "entries": [
-                    {
-                        "pr_number": 848,
-                        "head_branch": "fix/issue-844-exclude-epic-containers",
-                        "remote_branch": {"safe_to_delete_remote": True},
-                        "local_worktree": {
-                            "safe_to_remove_worktree": True,
-                            "worktree_path": worktree_path,
-                        },
-                        "planned_execution_order": [
-                            {"action": "remove_local_worktree", "phase": 1},
-                            {"action": "reassess_branch_ownership", "phase": 2},
-                            {"action": "delete_remote_branch", "phase": 3},
-                        ],
-                    }
-                ],
-                "reviewer_scratch_entries": [
-                    # Foreign scratch must be filtered before report execute loop;
-                    # if present here it would still be a test failure if acted on.
-                ],
-                "merged_pr_count": 1,
-            },
-        ).start()
-        patch(
-            "mcp_server.merged_cleanup_reconcile.remove_local_worktree",
-            side_effect=fake_remove,
-        ).start()
-        patch(
-            "mcp_server._collect_branch_ownership_records",
-            side_effect=fake_collect,
-        ).start()
-        patch("mcp_server._probe_remote_branch", side_effect=fake_probe).start()
-
-        res = gitea_reconcile_merged_cleanups(
-            dry_run=False,
-            execute_confirmed=True,
-            pr_number=848,
-            remote="prgs",
-            org="Scaled-Tech-Consulting",
-            repo="Gitea-Tools",
-        )
-        self.assertTrue(res.get("performed") or res.get("executed"))
-        self.assertEqual(res.get("selection_mode"), "exact_pr")
-        self.assertEqual(res.get("selected_pr_number"), 848)
-        actions = res.get("actions") or []
-        pr_numbers_touched = {
-            a.get("pr_number") for a in actions if a.get("pr_number") is not None
-        }
-        self.assertTrue(pr_numbers_touched.issubset({None, 848}) or not pr_numbers_touched)
-        removes = [a for a in actions if a.get("action") == "remove_local_worktree"]
-        deletes = [a for a in actions if a.get("action") == "delete_remote_branch"]
-        self.assertEqual(len(removes), 1)
-        self.assertEqual(remove_calls[0]["branch"], "fix/issue-844-exclude-epic-containers")
-        self.assertEqual(len(deletes), 1)
-        self.assertTrue(deletes[0].get("success"))
-        self.assertTrue(deletes[0].get("after_worktree_removal"))
-        self.assertEqual(len(delete_api_calls), 1)
-        self.assertEqual(
-            ownership_branches, ["fix/issue-844-exclude-epic-containers"]
-        )
-
-    def test_exact_pr_unknown_fails_closed_without_mutation(self):
-        from mcp_server import gitea_reconcile_merged_cleanups
-
-        def fake_api(method, url, *args, **kwargs):
-            if method == "GET" and "/pulls/99999" in url:
-                raise RuntimeError("HTTP 404 Not Found")
-            raise AssertionError(f"unexpected API call {method} {url}")
-
-        self.mock_api.side_effect = fake_api
-        res = gitea_reconcile_merged_cleanups(
-            dry_run=True,
-            pr_number=99999,
-            remote="prgs",
-        )
-        self.assertFalse(res.get("success"))
-        self.assertFalse(res.get("performed"))
-        self.assertEqual(res.get("blocker_kind"), "pr_unresolvable")
-        self.assertIn("99999", " ".join(res.get("reasons") or []))
-
-    def test_exact_pr_not_merged_fails_closed(self):
-        from mcp_server import gitea_reconcile_merged_cleanups
-
-        def fake_api(method, url, *args, **kwargs):
-            if method == "GET" and url.rstrip("/").endswith("/pulls/900"):
-                return {
-                    "number": 900,
-                    "merged": False,
-                    "merged_at": None,
-                    "state": "open",
-                    "head": {"ref": "feat/x", "sha": "a" * 40},
-                }
-            raise AssertionError(f"unexpected {method} {url}")
-
-        self.mock_api.side_effect = fake_api
-        res = gitea_reconcile_merged_cleanups(
-            dry_run=False,
-            execute_confirmed=True,
-            pr_number=900,
-            remote="prgs",
-        )
-        self.assertFalse(res.get("success"))
-        self.assertFalse(res.get("performed"))
-        self.assertEqual(res.get("blocker_kind"), "pr_not_merged")
-
-    def test_exact_pr_invalid_number_fails_closed(self):
-        from mcp_server import gitea_reconcile_merged_cleanups
-
-        res = gitea_reconcile_merged_cleanups(
-            dry_run=True,
-            pr_number=0,
-            remote="prgs",
-        )
-        self.assertFalse(res.get("success"))
-        self.assertEqual(res.get("blocker_kind"), "invalid_pr_number")
-        self.mock_api.assert_not_called()
-
-    def test_batch_mode_still_works_without_pr_number(self):
-        """Unfiltered batch path remains backward compatible."""
-        from mcp_server import gitea_reconcile_merged_cleanups
-
-        self.mock_all.side_effect = lambda url, auth, limit=None: []
-        self.mock_api.side_effect = lambda *a, **k: {}
-        patch(
-            "mcp_server.merged_cleanup_reconcile.build_reconciliation_report",
-            return_value={
-                "entries": [],
-                "reviewer_scratch_entries": [],
-                "merged_pr_count": 0,
-            },
-        ).start()
-        res = gitea_reconcile_merged_cleanups(dry_run=True, remote="prgs", limit=10)
-        self.assertTrue(res.get("success"))
-        self.assertEqual(res.get("selection_mode"), "batch")
-        self.assertIsNone(res.get("selected_pr_number"))
-

 if __name__ == "__main__":
    unittest.main()
@@ -0,0 +1,444 @@
+"""Task heartbeat through the native MCP author path (#790 Slice A, AC-N6).
+
+Assessor-level coverage is not sufficient here, and this project has already
+paid for learning that: in review #499 on PR #791 the #760 renewal waiver was
+computed correctly and then *discarded* at two later gates, so every real
+renewal still failed while the unit suite stayed green. AC-N6 exists because of
+that, and requires driving the real tools against a real git repository and a
+real durable lock file, composing the gates in production order.
+
+These tests therefore call ``gitea_lock_issue`` and
+``gitea_heartbeat_issue_lock`` themselves and assert on what lands on disk,
+never on an assessor's return value alone.
+"""
+
+from __future__ import annotations
+
+import os
+import subprocess
+import sys
+import tempfile
+import unittest
+from datetime import datetime, timedelta, timezone
+from unittest.mock import patch
+
+sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
+
+from mutation_profile_fixture import shared_mutation_env  # noqa: E402
+
+import issue_lock_provenance  # noqa: E402
+import issue_lock_store  # noqa: E402
+import lease_policy  # noqa: E402
+import mcp_server  # noqa: E402
+
+ISSUE = 9791
+BRANCH = f"fix/issue-{ISSUE}-heartbeat-mcp"
+IDENTITY = "example-user"
+PROFILE = "test-author-prgs"
+ORG = "Scaled-Tech-Consulting"
+REPO = "Gitea-Tools"
+
+
+def _ts(moment: datetime) -> str:
+    return (
+        moment.astimezone(timezone.utc)
+        .replace(microsecond=0)
+        .isoformat()
+        .replace("+00:00", "Z")
+    )
+
+
+class _HeartbeatMcpBase(unittest.TestCase):
+    """Real git repo plus a real durable lock, driven through the real tools."""
+
+    def setUp(self):
+        self.lock_dir = tempfile.TemporaryDirectory()
+        self.addCleanup(self.lock_dir.cleanup)
+        self.repo = tempfile.mkdtemp(prefix="issue790-mcp-")
+        self.addCleanup(lambda: subprocess.run(["rm", "-rf", self.repo], check=False))
+        self._init_worktree()
+        self.remotes = patch.dict(
+            mcp_server.REMOTES,
+            {"prgs": {"host": "gitea.prgs.cc", "org": ORG, "repo": REPO}},
+        )
+        self.remotes.start()
+        self.addCleanup(patch.stopall)
+        mcp_server._IDENTITY_CACHE.clear()
+
+    def _git(self, *args):
+        return subprocess.run(
+            ["git", "-C", self.repo, *args], capture_output=True, text=True, check=True
+        )
+
+    def _init_worktree(self):
+        self._git("init", "-q", "-b", "master")
+        self._git("config", "user.email", "[email protected]")
+        self._git("config", "user.name", "Test")
+        with open(os.path.join(self.repo, "seed.txt"), "w") as fh:
+            fh.write("seed\n")
+        self._git("add", "seed.txt")
+        self._git("commit", "-q", "-m", "seed")
+        self.base_sha = self._git("rev-parse", "HEAD").stdout.strip()
+        # A fresh claim starts base-equivalent, which is the ordinary first-lock
+        # shape and exercises assess_issue_lock_worktree on its normal path.
+        self._git("checkout", "-q", "-b", BRANCH)
+        self.head_sha = self.base_sha
+        self.worktree = os.path.realpath(self.repo)
+
+    def _lock_path(self):
+        return issue_lock_store.lock_file_path(
+            remote="prgs",
+            org=ORG,
+            repo=REPO,
+            issue_number=ISSUE,
+            lock_dir=self.lock_dir.name,
+        )
+
+    def _tool_env(self):
+        env = shared_mutation_env(
+            PROFILE, include_example_repo=True, GITEA_ISSUE_LOCK_DIR=self.lock_dir.name
+        )
+        env["GITEA_ISSUE_LOCK_DIR"] = self.lock_dir.name
+        return env
+
+    def _git_state(self, *, porcelain="", base_equivalent=True):
+        return {
+            "current_branch": BRANCH,
+            "porcelain_status": porcelain,
+            "base_equivalent": base_equivalent,
+            "head_sha": self.head_sha,
+            "inspected_git_root": self.worktree,
+            "base_branch": "master",
+        }
+
+    def run_lock_issue(
+        self,
+        *,
+        branch_entries=None,
+        open_prs=None,
+        git_state=None,
+        identity=IDENTITY,
+        profile=PROFILE,
+    ):
+        branch_entries = branch_entries if branch_entries is not None else []
+        open_prs = open_prs if open_prs is not None else []
+        git_state = git_state or self._git_state()
+        env = self._tool_env()
+        with patch(
+            "mcp_server.api_get_all", return_value=list(branch_entries)
+        ), patch(
+            "mcp_server._list_open_pulls", return_value=list(open_prs)
+        ), patch(
+            "mcp_server.get_auth_header", return_value="token x"
+        ), patch(
+            "mcp_server._work_lease_claimant",
+            return_value={"username": identity, "profile": profile},
+        ), patch(
+            "mcp_server.issue_lock_worktree.read_worktree_git_state",
+            return_value=git_state,
+        ), patch(
+            "mcp_server.issue_duplicate_context_fetcher",
+            side_effect=lambda h, o, r, auth, issue_number: (
+                list(open_prs),
+                [b.get("name") for b in branch_entries if isinstance(b, dict)],
+                {"status": "not_claimed"},
+            ),
+        ), patch.dict(os.environ, env, clear=True):
+            os.environ["GITEA_ISSUE_LOCK_DIR"] = self.lock_dir.name
+            return mcp_server.gitea_lock_issue(
+                issue_number=ISSUE,
+                branch_name=BRANCH,
+                remote="prgs",
+                worktree_path=self.worktree,
+            )
+
+    def run_heartbeat(
+        self, *, task_session_id, identity=IDENTITY, profile=PROFILE, **kwargs
+    ):
+        env = self._tool_env()
+        with patch(
+            "mcp_server._work_lease_claimant",
+            return_value={"username": identity, "profile": profile},
+        ), patch("mcp_server.get_auth_header", return_value="token x"), patch.dict(
+            os.environ, env, clear=True
+        ):
+            os.environ["GITEA_ISSUE_LOCK_DIR"] = self.lock_dir.name
+            return mcp_server.gitea_heartbeat_issue_lock(
+                issue_number=ISSUE,
+                branch_name=kwargs.pop("branch_name", BRANCH),
+                task_session_id=task_session_id,
+                remote="prgs",
+                worktree_path=kwargs.pop("worktree_path", self.worktree),
+                **kwargs,
+            )
+
+    def write_legacy_lock(self, *, hours_old: float = 3.0, ttl_hours: float = 4.0):
+        """A durable lock in the shape the store wrote before this slice."""
+        now = datetime.now(timezone.utc)
+        claimant = {"username": IDENTITY, "profile": PROFILE}
+        created = now - timedelta(hours=hours_old)
+        record = {
+            "issue_number": ISSUE,
+            "branch_name": BRANCH,
+            "remote": "prgs",
+            "org": ORG,
+            "repo": REPO,
+            "worktree_path": self.worktree,
+            "session_pid": os.getpid(),
+            "pid": os.getpid(),
+            "lock_generation": 1,
+            "work_lease": {
+                "operation_type": issue_lock_store.AUTHOR_ISSUE_WORK_LEASE,
+                "issue_number": ISSUE,
+                "pr_number": None,
+                "branch": BRANCH,
+                "worktree_path": self.worktree,
+                "claimant": claimant,
+                "created_at": _ts(created),
+                # The legacy signature: never advanced past creation.
+                "last_heartbeat_at": _ts(created),
+                "expires_at": _ts(created + timedelta(hours=ttl_hours)),
+            },
+            "lock_provenance": issue_lock_provenance.build_sanctioned_lock_provenance(
+                tool="gitea_lock_issue", claimant=claimant
+            ),
+        }
+        path = self._lock_path()
+        record["lock_file_path"] = path
+        issue_lock_store.save_lock_file(path, record)
+        return record
+
+
+class TestLockIssueMintsTheLifecycle(_HeartbeatMcpBase):
+    """Durable lock creation and read-back through the real tool."""
+
+    def test_native_lock_writes_the_marker_and_a_task_session_id(self):
+        result = self.run_lock_issue()
+        self.assertTrue(result["success"], result)
+
+        written = issue_lock_store.read_lock_file(result["lock_file_path"])
+        lease = written["work_lease"]
+        self.assertEqual(
+            lease["lifecycle_version"], lease_policy.LIFECYCLE_HEARTBEAT_V1
+        )
+        self.assertTrue(lease["task_session_id"])
+        self.assertFalse(issue_lock_store.is_legacy_lease(written))
+        # AC-N1: the ownership key is not the daemon pid, which is recorded
+        # separately as evidence.
+        self.assertNotIn(str(written["session_pid"]), lease["task_session_id"])
+        self.assertEqual(written["session_pid"], os.getpid())
+
+    def test_native_lease_uses_the_policy_window_not_four_hours(self):
+        result = self.run_lock_issue()
+        lease = result["work_lease"]
+        created = datetime.fromisoformat(lease["created_at"].replace("Z", "+00:00"))
+        expires = datetime.fromisoformat(lease["expires_at"].replace("Z", "+00:00"))
+        policy = lease_policy.policy_for(lease_policy.TASK_CLASS_AUTHOR_ISSUE_WORK)
+        self.assertEqual(
+            (expires - created).total_seconds() / 60.0, policy.initial_ttl_minutes
+        )
+
+    def test_freshness_of_a_new_native_lock_is_live(self):
+        result = self.run_lock_issue()
+        self.assertEqual(
+            result["lock_freshness"]["status"], issue_lock_store.STATUS_LIVE
+        )
+        self.assertTrue(result["lock_freshness"]["live"])
+
+
+class TestHeartbeatThroughTheTool(_HeartbeatMcpBase):
+    def _lock_and_session(self):
+        result = self.run_lock_issue()
+        self.assertTrue(result["success"], result)
+        return result, result["work_lease"]["task_session_id"]
+
+    def test_heartbeat_slides_the_lease_and_advances_the_generation(self):
+        locked, session = self._lock_and_session()
+        before = issue_lock_store.read_lock_file(locked["lock_file_path"])
+
+        beat = self.run_heartbeat(task_session_id=session)
+
+        self.assertTrue(beat["success"], beat)
+        self.assertEqual(beat["operation"], "heartbeat")
+        after = issue_lock_store.read_lock_file(locked["lock_file_path"])
+        self.assertGreater(
+            issue_lock_store.lock_generation(after),
+            issue_lock_store.lock_generation(before),
+        )
+        self.assertGreaterEqual(
+            after["work_lease"]["expires_at"], before["work_lease"]["expires_at"]
+        )
+        self.assertEqual(after["work_lease"]["heartbeat_count"], 2)
+
+    def test_heartbeat_evidence_survives_the_downstream_mutation_gate(self):
+        """The #499 F2 lesson, applied.
+
+        A sanction that is computed and then discarded downstream is worthless.
+        After a heartbeat the lock must still satisfy the gate every author
+        mutation runs through.
+        """
+        locked, session = self._lock_and_session()
+        self.run_heartbeat(task_session_id=session)
+
+        written = issue_lock_store.read_lock_file(locked["lock_file_path"])
+        verdict = issue_lock_store.verify_lock_for_mutation(
+            written,
+            issue_number=ISSUE,
+            branch_name=BRANCH,
+            worktree_path=self.worktree,
+        )
+        self.assertTrue(verdict["proven"], verdict)
+        self.assertFalse(verdict["block"])
+
+    def _duplicate_gate(self, *, open_prs, branches):
+        env = self._tool_env()
+        with patch("mcp_server.get_auth_header", return_value="token x"), patch(
+            "mcp_server.issue_duplicate_context_fetcher",
+            side_effect=lambda h, o, r, auth, issue_number: (
+                list(open_prs),
+                list(branches),
+                {"status": "not_claimed"},
+            ),
+        ), patch.dict(os.environ, env, clear=True):
+            os.environ["GITEA_ISSUE_LOCK_DIR"] = self.lock_dir.name
+            return mcp_server.gitea_assess_work_issue_duplicate(
+                issue_number=ISSUE, branch_name=BRANCH, remote="prgs"
+            )
+
+    def test_heartbeat_does_not_change_the_duplicate_gate_verdict(self):
+        """The gate must be invariant under heartbeating.
+
+        The point is not that the gate passes — with a linked open PR at the
+        lock phase it correctly blocks (#400), heartbeat or not. The property
+        that matters is that sliding a lease neither loosens the gate nor
+        corrupts the lock state it reads: the verdict before and after a
+        heartbeat must be identical, for both the clear and the blocking shape.
+        """
+        _, session = self._lock_and_session()
+        linked = [{"number": 4242, "head": {"ref": BRANCH, "sha": self.head_sha}}]
+
+        clear_before = self._duplicate_gate(open_prs=[], branches=[])
+        blocked_before = self._duplicate_gate(open_prs=linked, branches=[BRANCH])
+
+        self.assertTrue(self.run_heartbeat(task_session_id=session)["success"])
+
+        clear_after = self._duplicate_gate(open_prs=[], branches=[])
+        blocked_after = self._duplicate_gate(open_prs=linked, branches=[BRANCH])
+
+        self.assertEqual(clear_before["outcome"], clear_after["outcome"])
+        self.assertFalse(clear_after["block"])
+        self.assertEqual(blocked_before["outcome"], blocked_after["outcome"])
+        self.assertTrue(blocked_after["block"])
+        self.assertEqual(blocked_after["linked_open_pr"], 4242)
+
+    def test_foreign_session_id_is_refused_through_the_tool(self):
+        self._lock_and_session()
+        beat = self.run_heartbeat(task_session_id="author_issue_work-ffffffffffffffff")
+        self.assertFalse(beat["success"])
+        self.assertIn("task_session_id does not match", " ".join(beat["reasons"]))
+
+    def test_stale_generation_is_refused_through_the_tool(self):
+        locked, session = self._lock_and_session()
+        current = issue_lock_store.lock_generation(
+            issue_lock_store.read_lock_file(locked["lock_file_path"])
+        )
+        beat = self.run_heartbeat(
+            task_session_id=session, expected_generation=current + 5
+        )
+        self.assertFalse(beat["success"])
+        self.assertIn("generation changed", beat["reasons"][0])
+
+    def test_foreign_claimant_is_refused_through_the_tool(self):
+        _, session = self._lock_and_session()
+        beat = self.run_heartbeat(task_session_id=session, identity="someone-else")
+        self.assertFalse(beat["success"])
+
+    def test_heartbeat_cannot_acquire_a_missing_lock(self):
+        beat = self.run_heartbeat(task_session_id="author_issue_work-000000000000")
+        self.assertFalse(beat["success"])
+        self.assertIn("no durable lock", beat["reasons"][0])
+
+    def test_alive_pid_alone_does_not_keep_a_lease_live_through_the_tool(self):
+        """PID-only refusal, end to end.
+
+        The recorded pid is this live process. The lock is aged past its grace
+        with no heartbeat, so the tool must refuse to slide it and the durable
+        record must classify as a missed heartbeat rather than as live.
+        """
+        locked, session = self._lock_and_session()
+        record = issue_lock_store.read_lock_file(locked["lock_file_path"])
+        record["work_lease"]["last_heartbeat_at"] = _ts(
+            datetime.now(timezone.utc) - timedelta(minutes=30)
+        )
+        record["work_lease"]["expires_at"] = _ts(
+            datetime.now(timezone.utc) + timedelta(hours=2)
+        )
+        issue_lock_store.save_lock_file(locked["lock_file_path"], record)
+
+        self.assertTrue(issue_lock_store.is_process_alive(record["session_pid"]))
+        fresh = issue_lock_store.assess_lock_freshness(record)
+        self.assertEqual(
+            fresh["status"], issue_lock_store.STATUS_STALE_MISSED_HEARTBEAT
+        )
+        self.assertTrue(fresh["pid_alive"])
+
+        beat = self.run_heartbeat(task_session_id=session)
+        self.assertFalse(beat["success"])
+        self.assertIn("reclaimed", " ".join(beat["reasons"]))
+
+
+class TestLegacyLocksThroughTheTool(_HeartbeatMcpBase):
+    """AC-N8 end to end: protected on deployment, and rebindable."""
+
+    def test_legacy_lock_stays_protected_after_deployment(self):
+        record = self.write_legacy_lock(hours_old=3.0, ttl_hours=4.0)
+        fresh = issue_lock_store.assess_lock_freshness(record)
+        self.assertEqual(fresh["status"], issue_lock_store.STATUS_LIVE)
+        self.assertTrue(fresh["legacy_lease"])
+        self.assertTrue(fresh["legacy_expiry_preserved"])
+        # It had never heartbeated, so under the new grace alone it would be
+        # long gone; the preserved absolute expiry is what protects it.
+        self.assertEqual(
+            record["work_lease"]["created_at"],
+            record["work_lease"]["last_heartbeat_at"],
+        )
+
+    def test_tool_rebinds_a_legacy_lock_and_mints_a_first_heartbeat(self):
+        self.write_legacy_lock(hours_old=3.0, ttl_hours=4.0)
+
+        result = self.run_heartbeat(task_session_id=None)
+
+        self.assertTrue(result["success"], result)
+        self.assertEqual(result["operation"], "legacy_rebind")
+        self.assertTrue(result["task_session_id"])
+
+        written = issue_lock_store.read_lock_file(self._lock_path())
+        lease = written["work_lease"]
+        self.assertEqual(
+            lease["lifecycle_version"], lease_policy.LIFECYCLE_HEARTBEAT_V1
+        )
+        self.assertEqual(lease["heartbeat_count"], 1)
+        self.assertNotEqual(
+            lease["created_at"],
+            written["legacy_rebind"]["legacy_origin"]["created_at"],
+        )
+        self.assertFalse(issue_lock_store.is_legacy_lease(written))
+
+    def test_rebound_lock_then_heartbeats_through_the_tool(self):
+        self.write_legacy_lock(hours_old=3.0, ttl_hours=4.0)
+        rebound = self.run_heartbeat(task_session_id=None)
+        beat = self.run_heartbeat(task_session_id=rebound["task_session_id"])
+        self.assertTrue(beat["success"], beat)
+        self.assertEqual(beat["operation"], "heartbeat")
+        self.assertEqual(beat["heartbeat_count"], 2)
+
+    def test_rebind_refuses_a_foreign_owner_through_the_tool(self):
+        self.write_legacy_lock(hours_old=3.0, ttl_hours=4.0)
+        result = self.run_heartbeat(task_session_id=None, identity="someone-else")
+        self.assertFalse(result["success"])
+        self.assertEqual(result["operation"], "legacy_rebind")
+
+
+if __name__ == "__main__":
+    unittest.main()
@@ -0,0 +1,594 @@
+"""Central lease policy and load-bearing heartbeat freshness (#790 Slice A).
+
+Before this slice, ``issue_lock_store.assess_lock_freshness`` parsed
+``last_heartbeat_at`` and then never consulted it: liveness was decided by an
+absolute four-hour ``expires_at`` and by PID liveness. Because the recorded PID
+is the long-lived MCP daemon rather than the authoring task, an abandoned claim
+stayed "live" for the full four hours, and a claim whose work had already landed
+blocked reconciliation for just as long (Issue #787 / PR #789, and again Issue
+#760 / PR #791).
+
+These tests pin the corrected semantics, including the two asymmetries that are
+easy to lose in a refactor:
+
+* an **alive** PID must never make anything live (AC-N2), while
+* a **dead** PID must still mark a lease stale, because #753 dead-session
+  recovery keys on exactly that classification.
+
+Durable-state helpers here write real lock files through the real flock path;
+they are not mocks of the store.
+"""
+
+from __future__ import annotations
+
+import os
+import sys
+import tempfile
+import unittest
+from datetime import datetime, timedelta, timezone
+from unittest.mock import patch
+
+sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+
+import issue_lock_store  # noqa: E402
+import lease_policy  # noqa: E402
+import pr_work_lease  # noqa: E402
+import reviewer_pr_lease  # noqa: E402
+
+ISSUE = 9790
+BRANCH = f"fix/issue-{ISSUE}-heartbeat"
+IDENTITY = "example-user"
+PROFILE = "test-author-prgs"
+ORG = "Example-Org"
+REPO = "Example-Repo"
+REMOTE = "prgs"
+DEAD_PID = 2**22  # far above any live pid on a test host
+
+
+def _ts(moment: datetime) -> str:
+    return (
+        moment.astimezone(timezone.utc)
+        .replace(microsecond=0)
+        .isoformat()
+        .replace("+00:00", "Z")
+    )
+
+
+class _LockFixture(unittest.TestCase):
+    def setUp(self):
+        self.lock_dir = tempfile.TemporaryDirectory()
+        self.addCleanup(self.lock_dir.cleanup)
+        self.now = datetime.now(timezone.utc)
+        self.worktree = os.path.realpath(tempfile.mkdtemp(prefix="issue790-"))
+        self.addCleanup(patch.stopall)
+
+    def _path(self):
+        return issue_lock_store.lock_file_path(
+            remote=REMOTE,
+            org=ORG,
+            repo=REPO,
+            issue_number=ISSUE,
+            lock_dir=self.lock_dir.name,
+        )
+
+    def write_lock(
+        self,
+        *,
+        lifecycle: str | None = lease_policy.LIFECYCLE_HEARTBEAT_V1,
+        created_delta: timedelta = timedelta(minutes=1),
+        heartbeat_delta: timedelta = timedelta(minutes=1),
+        expires_delta: timedelta = timedelta(minutes=9),
+        pid: int | None = None,
+        task_session_id: str | None = "author_issue_work-aaaabbbbccccdddd",
+        generation: int = 1,
+        identity: str = IDENTITY,
+        profile: str = PROFILE,
+        branch: str = BRANCH,
+        worktree: str | None = None,
+    ) -> dict:
+        """Write a real durable lock and return the record.
+
+        Deltas are relative to ``self.now``; ``expires_delta`` is added, the
+        others subtracted, so "in the past" reads naturally at each call site.
+        """
+        lease: dict = {
+            "operation_type": issue_lock_store.AUTHOR_ISSUE_WORK_LEASE,
+            "issue_number": ISSUE,
+            "pr_number": None,
+            "branch": branch,
+            "worktree_path": worktree or self.worktree,
+            "claimant": {"username": identity, "profile": profile},
+            "created_at": _ts(self.now - created_delta),
+            "last_heartbeat_at": _ts(self.now - heartbeat_delta),
+            "expires_at": _ts(self.now + expires_delta),
+        }
+        if lifecycle is not None:
+            lease["lifecycle_version"] = lifecycle
+            if task_session_id is not None:
+                lease["task_session_id"] = task_session_id
+        pid_value = os.getpid() if pid is None else pid
+        record = {
+            "issue_number": ISSUE,
+            "branch_name": branch,
+            "remote": REMOTE,
+            "org": ORG,
+            "repo": REPO,
+            "worktree_path": worktree or self.worktree,
+            "session_pid": pid_value,
+            "pid": pid_value,
+            "lock_generation": generation,
+            "work_lease": lease,
+        }
+        path = self._path()
+        record["lock_file_path"] = path
+        issue_lock_store.save_lock_file(path, record)
+        return record
+
+
+class TestPolicyIsTheSingleSource(unittest.TestCase):
+    """AC-N7: one authoritative configuration source for every duration."""
+
+    def test_author_policy_carries_the_agreed_values(self):
+        policy = lease_policy.policy_for(lease_policy.TASK_CLASS_AUTHOR_ISSUE_WORK)
+        self.assertEqual(policy.initial_ttl_minutes, 10.0)
+        self.assertEqual(policy.heartbeat_cadence_minutes, 2.0)
+        self.assertEqual(policy.stale_warning_minutes, 5.0)
+        self.assertEqual(policy.missed_heartbeat_grace_minutes, 10.0)
+        self.assertEqual(policy.absolute_cap_hours, 8.0)
+        self.assertEqual(policy.recovery_grace_minutes, 10.0)
+        self.assertEqual(policy.terminal_race_drain_minutes, 2.0)
+        self.assertTrue(policy.terminal_retirement_eligible)
+        self.assertTrue(policy.heartbeat_lifecycle_active)
+
+    def test_the_four_hour_author_ttl_literal_is_gone(self):
+        """The duplicated literal AC-N7 exists to remove."""
+        self.assertFalse(hasattr(issue_lock_store, "WORK_LEASE_TTL_HOURS"))
+        import gitea_mcp_server
+
+        self.assertFalse(hasattr(gitea_mcp_server, "WORK_LEASE_TTL_HOURS"))
+
+    def test_declared_reviewer_values_match_the_module_still_using_them(self):
+        """Slice A declares reviewer/merger numbers without rewiring them.
+
+        Recording a value in two places is only safe if drift is detectable, so
+        this asserts the declaration still equals the constants #747 owns. When
+        Slice C migrates those call sites, this test becomes the proof the
+        migration changed nothing.
+        """
+        policy = lease_policy.policy_for(lease_policy.TASK_CLASS_REVIEWER_PR)
+        self.assertEqual(
+            policy.initial_ttl_minutes, float(reviewer_pr_lease.LEASE_TTL_MINUTES)
+        )
+        self.assertEqual(
+            policy.stale_warning_minutes,
+            float(reviewer_pr_lease.STALE_WARNING_MINUTES),
+        )
+        self.assertFalse(policy.heartbeat_lifecycle_active)
+
+    def test_declared_conflict_fix_value_matches_its_module(self):
+        policy = lease_policy.policy_for(lease_policy.TASK_CLASS_CONFLICT_FIX)
+        self.assertEqual(
+            policy.initial_ttl_minutes,
+            float(pr_work_lease.DEFAULT_CONFLICT_FIX_TTL_MINUTES),
+        )
+        self.assertFalse(policy.heartbeat_lifecycle_active)
+
+    def test_environment_override_applies(self):
+        var = lease_policy.env_var_name(
+            lease_policy.TASK_CLASS_AUTHOR_ISSUE_WORK, "initial_ttl_minutes"
+        )
+        with patch.dict(os.environ, {var: "7"}):
+            self.assertEqual(
+                lease_policy.policy_for(
+                    lease_policy.TASK_CLASS_AUTHOR_ISSUE_WORK
+                ).initial_ttl_minutes,
+                7.0,
+            )
+
+    def test_unusable_override_falls_back_instead_of_minting_a_zero_lease(self):
+        """A typo must not make every claim instantly reclaimable."""
+        var = lease_policy.env_var_name(
+            lease_policy.TASK_CLASS_AUTHOR_ISSUE_WORK, "initial_ttl_minutes"
+        )
+        for bad in ("0", "-5", "not-a-number", "   "):
+            with self.subTest(value=bad), patch.dict(os.environ, {var: bad}):
+                self.assertEqual(
+                    lease_policy.policy_for(
+                        lease_policy.TASK_CLASS_AUTHOR_ISSUE_WORK
+                    ).initial_ttl_minutes,
+                    10.0,
+                )
+
+    def test_unknown_task_class_does_not_raise(self):
+        policy = lease_policy.policy_for("something-new")
+        self.assertEqual(policy.task_class, lease_policy.TASK_CLASS_AUTHOR_ISSUE_WORK)
+
+
+class TestLifecycleDiscrimination(_LockFixture):
+    """AC-N8: the marker, never a timestamp, decides legacy vs heartbeat."""
+
+    def test_missing_marker_reads_as_legacy(self):
+        record = self.write_lock(lifecycle=None)
+        self.assertTrue(issue_lock_store.is_legacy_lease(record))
+        self.assertEqual(
+            issue_lock_store.lease_lifecycle_version(record),
+            lease_policy.LIFECYCLE_LEGACY,
+        )
+
+    def test_marker_present_reads_as_heartbeat_lifecycle(self):
+        record = self.write_lock()
+        self.assertFalse(issue_lock_store.is_legacy_lease(record))
+
+    def test_equal_created_and_heartbeat_never_implies_a_fresh_heartbeat(self):
+        """The exact inversion AC-N8 forbids.
+
+        A legacy lock has ``last_heartbeat_at == created_at`` forever because
+        nothing ever advanced it. Reading that equality as "recently
+        heartbeated" would classify every never-heartbeated lock as fresh.
+        """
+        legacy = self.write_lock(
+            lifecycle=None,
+            created_delta=timedelta(hours=3),
+            heartbeat_delta=timedelta(hours=3),
+        )
+        lease = legacy["work_lease"]
+        self.assertEqual(lease["created_at"], lease["last_heartbeat_at"])
+        self.assertTrue(issue_lock_store.is_legacy_lease(legacy))
+
+        # A brand-new heartbeat lease has them equal too, so the equality
+        # carries no information in either direction.
+        fresh = self.write_lock(
+            created_delta=timedelta(seconds=0), heartbeat_delta=timedelta(seconds=0)
+        )
+        self.assertEqual(
+            fresh["work_lease"]["created_at"],
+            fresh["work_lease"]["last_heartbeat_at"],
+        )
+        self.assertFalse(issue_lock_store.is_legacy_lease(fresh))
+
+    def test_minted_session_id_contains_no_pid(self):
+        """AC-N1: the ownership key must not be derived from the daemon pid."""
+        minted = issue_lock_store.mint_task_session_id()
+        self.assertNotIn(str(os.getpid()), minted)
+        self.assertNotEqual(minted, issue_lock_store.mint_task_session_id())
+
+
+class TestFreshnessIsHeartbeatDriven(_LockFixture):
+    """AC-N2 and the new bands."""
+
+    def test_fresh_heartbeat_is_live(self):
+        record = self.write_lock(heartbeat_delta=timedelta(minutes=1))
+        fresh = issue_lock_store.assess_lock_freshness(record, now=self.now)
+        self.assertEqual(fresh["status"], issue_lock_store.STATUS_LIVE)
+        self.assertTrue(fresh["live"])
+        self.assertFalse(fresh["heartbeat_warning"])
+
+    def test_heartbeat_past_warning_is_still_live_but_flagged(self):
+        record = self.write_lock(heartbeat_delta=timedelta(minutes=6))
+        fresh = issue_lock_store.assess_lock_freshness(record, now=self.now)
+        self.assertEqual(fresh["status"], issue_lock_store.STATUS_LIVE)
+        self.assertTrue(fresh["heartbeat_warning"])
+
+    def test_missed_heartbeat_past_grace_is_classified_explicitly(self):
+        record = self.write_lock(
+            heartbeat_delta=timedelta(minutes=11),
+            expires_delta=timedelta(minutes=30),
+        )
+        fresh = issue_lock_store.assess_lock_freshness(record, now=self.now)
+        self.assertEqual(
+            fresh["status"], issue_lock_store.STATUS_STALE_MISSED_HEARTBEAT
+        )
+        self.assertFalse(fresh["live"])
+        self.assertTrue(fresh["stale"])
+
+    def test_alive_pid_never_establishes_freshness(self):
+        """The defect in one assertion.
+
+        The recorded PID is this very process, so it is unambiguously alive —
+        and the lease is still not live, because the task stopped heartbeating.
+        """
+        record = self.write_lock(
+            pid=os.getpid(),
+            heartbeat_delta=timedelta(hours=4),
+            expires_delta=timedelta(hours=4),
+        )
+        fresh = issue_lock_store.assess_lock_freshness(record, now=self.now)
+        self.assertTrue(fresh["pid_alive"])
+        self.assertFalse(fresh["live"])
+        self.assertEqual(
+            fresh["status"], issue_lock_store.STATUS_STALE_MISSED_HEARTBEAT
+        )
+
+    def test_dead_pid_still_marks_stale_for_issue_753(self):
+        """The opposite asymmetry: dead-PID corroboration is preserved."""
+        record = self.write_lock(pid=DEAD_PID, heartbeat_delta=timedelta(minutes=1))
+        fresh = issue_lock_store.assess_lock_freshness(record, now=self.now)
+        self.assertEqual(fresh["status"], issue_lock_store.STATUS_STALE)
+        self.assertFalse(fresh["live"])
+        self.assertIn("not alive", fresh["reason"])
+
+    def test_absolute_cap_requires_readoption(self):
+        record = self.write_lock(
+            created_delta=timedelta(hours=9), heartbeat_delta=timedelta(minutes=1)
+        )
+        fresh = issue_lock_store.assess_lock_freshness(record, now=self.now)
+        self.assertEqual(fresh["status"], issue_lock_store.STATUS_STALE_ABSOLUTE_CAP)
+        self.assertIn("re-adoption", fresh["reason"])
+
+    def test_heartbeat_lifecycle_without_a_heartbeat_fails_closed(self):
+        record = self.write_lock()
+        del record["work_lease"]["last_heartbeat_at"]
+        issue_lock_store.save_lock_file(self._path(), record)
+        fresh = issue_lock_store.assess_lock_freshness(record, now=self.now)
+        self.assertEqual(
+            fresh["status"], issue_lock_store.STATUS_STALE_MISSED_HEARTBEAT
+        )
+        self.assertIn("fail closed", fresh["reason"])
+
+    def test_absent_lock(self):
+        fresh = issue_lock_store.assess_lock_freshness(None)
+        self.assertEqual(fresh["status"], issue_lock_store.STATUS_ABSENT)
+        self.assertFalse(fresh["stale"])
+
+
+class TestLegacyLocksStayProtected(_LockFixture):
+    """AC-N8: deployment must not retroactively shorten an existing claim."""
+
+    def test_legacy_lock_with_a_stale_heartbeat_remains_live(self):
+        """The deployment-safety case.
+
+        A four-hour legacy lease minted three hours ago has not heartbeated
+        once. Under the new grace it would be long gone; under its preserved
+        absolute expiry it is still live, and must stay that way.
+        """
+        record = self.write_lock(
+            lifecycle=None,
+            created_delta=timedelta(hours=3),
+            heartbeat_delta=timedelta(hours=3),
+            expires_delta=timedelta(hours=1),
+        )
+        fresh = issue_lock_store.assess_lock_freshness(record, now=self.now)
+        self.assertEqual(fresh["status"], issue_lock_store.STATUS_LIVE)
+        self.assertTrue(fresh["live"])
+        self.assertTrue(fresh["legacy_lease"])
+        self.assertTrue(fresh["legacy_expiry_preserved"])
+
+    def test_legacy_lock_past_its_absolute_expiry_is_expired_as_before(self):
+        record = self.write_lock(
+            lifecycle=None,
+            created_delta=timedelta(hours=5),
+            heartbeat_delta=timedelta(hours=5),
+            expires_delta=timedelta(hours=-1),
+        )
+        fresh = issue_lock_store.assess_lock_freshness(record, now=self.now)
+        self.assertEqual(fresh["status"], issue_lock_store.STATUS_EXPIRED)
+
+    def test_legacy_lock_is_never_reclaimed_by_the_heartbeat_band(self):
+        record = self.write_lock(
+            lifecycle=None,
+            created_delta=timedelta(hours=3),
+            heartbeat_delta=timedelta(hours=3),
+            expires_delta=timedelta(hours=1),
+        )
+        reclaim = issue_lock_store.assess_expired_lock_reclaim(record, now=self.now)
+        self.assertFalse(reclaim["reclaim_allowed"])
+
+
+class TestReclaimAfterMissedHeartbeat(_LockFixture):
+    def test_missed_heartbeat_makes_ownership_reclaimable(self):
+        record = self.write_lock(
+            pid=os.getpid(),
+            heartbeat_delta=timedelta(minutes=15),
+            expires_delta=timedelta(hours=3),
+        )
+        reclaim = issue_lock_store.assess_expired_lock_reclaim(record, now=self.now)
+        self.assertTrue(reclaim["reclaim_allowed"])
+        self.assertIn("stale_missed_heartbeat", reclaim["reasons"][0])
+
+    def test_live_lease_is_never_reclaimable(self):
+        record = self.write_lock(heartbeat_delta=timedelta(minutes=1))
+        reclaim = issue_lock_store.assess_expired_lock_reclaim(record, now=self.now)
+        self.assertFalse(reclaim["reclaim_allowed"])
+
+    def test_dead_pid_reclaim_path_is_unchanged(self):
+        """#753 must keep working through its original conditions."""
+        record = self.write_lock(pid=DEAD_PID, heartbeat_delta=timedelta(minutes=1))
+        reclaim = issue_lock_store.assess_expired_lock_reclaim(record, now=self.now)
+        self.assertTrue(reclaim["reclaim_allowed"])
+        self.assertTrue(reclaim["owner_pid_dead"])
+
+
+class TestHeartbeatWriter(_LockFixture):
+    """A4: flock + CAS + exact verification, and no revival path."""
+
+    def _heartbeat(self, **kwargs):
+        params = {
+            "remote": REMOTE,
+            "org": ORG,
+            "repo": REPO,
+            "issue_number": ISSUE,
+            "branch_name": BRANCH,
+            "worktree_path": self.worktree,
+            "identity": IDENTITY,
+            "profile": PROFILE,
+            "task_session_id": "author_issue_work-aaaabbbbccccdddd",
+            "lock_dir": self.lock_dir.name,
+            "now": self.now,
+        }
+        params.update(kwargs)
+        return issue_lock_store.heartbeat_session_lock(**params)
+
+    def test_heartbeat_slides_expiry_and_advances_generation(self):
+        self.write_lock(heartbeat_delta=timedelta(minutes=4), generation=5)
+        result = self._heartbeat()
+        self.assertTrue(result["success"], result)
+        self.assertEqual(result["prior_generation"], 5)
+        self.assertEqual(result["lock_generation"], 6)
+        self.assertEqual(result["heartbeat_count"], 1)
+        self.assertEqual(result["last_heartbeat_at"], _ts(self.now))
+        self.assertEqual(result["expires_at"], _ts(self.now + timedelta(minutes=10)))
+        self.assertTrue(result["freshness"]["live"])
+
+    def test_heartbeat_is_durable_and_repeatable(self):
+        self.write_lock(heartbeat_delta=timedelta(minutes=4))
+        self._heartbeat()
+        second = self._heartbeat(now=self.now + timedelta(minutes=1))
+        self.assertTrue(second["success"], second)
+        self.assertEqual(second["heartbeat_count"], 2)
+        written = issue_lock_store.read_lock_file(self._path())
+        self.assertEqual(written["work_lease"]["heartbeat_count"], 2)
+
+    def test_stale_generation_is_refused(self):
+        self.write_lock(generation=5)
+        result = self._heartbeat(expected_generation=4)
+        self.assertFalse(result["success"])
+        self.assertIn("generation changed", result["reasons"][0])
+
+    def test_foreign_session_is_refused(self):
+        self.write_lock()
+        result = self._heartbeat(task_session_id="author_issue_work-ffffffffffffffff")
+        self.assertFalse(result["success"])
+        self.assertIn("task_session_id does not match", " ".join(result["reasons"]))
+
+    def test_missing_session_id_is_refused(self):
+        self.write_lock()
+        result = self._heartbeat(task_session_id="")
+        self.assertFalse(result["success"])
+
+    def test_foreign_claimant_is_refused(self):
+        self.write_lock()
+        for field, value in (
+            ("identity", "someone-else"),
+            ("profile", "other-profile"),
+        ):
+            with self.subTest(field=field):
+                result = self._heartbeat(**{field: value})
+                self.assertFalse(result["success"])
+
+    def test_branch_and_worktree_mismatch_are_refused(self):
+        self.write_lock()
+        wrong_branch = self._heartbeat(branch_name=f"fix/issue-{ISSUE}-other")
+        self.assertFalse(wrong_branch["success"])
+        wrong_worktree = self._heartbeat(worktree_path="/tmp/not-the-worktree")
+        self.assertFalse(wrong_worktree["success"])
+
+    def test_lapsed_lease_cannot_be_heartbeated_back_to_life(self):
+        """No revival path (A4).
+
+        A session that stopped proving liveness must reclaim under a fresh
+        generation, not restore ownership retroactively.
+        """
+        self.write_lock(
+            heartbeat_delta=timedelta(minutes=30), expires_delta=timedelta(hours=1)
+        )
+        result = self._heartbeat()
+        self.assertFalse(result["success"])
+        self.assertIn("reclaimed", " ".join(result["reasons"]))
+
+    def test_absent_lock_cannot_be_created_by_heartbeat(self):
+        result = self._heartbeat()
+        self.assertFalse(result["success"])
+        self.assertIn("no durable lock", result["reasons"][0])
+
+    def test_legacy_lock_is_refused_until_rebound(self):
+        self.write_lock(lifecycle=None)
+        result = self._heartbeat()
+        self.assertFalse(result["success"])
+        self.assertTrue(result["legacy_lease"])
+        self.assertIn("rebound", " ".join(result["reasons"]))
+
+
+class TestLegacyRebind(_LockFixture):
+    """AC-N8 exit route: canonical exact-owner rebinding."""
+
+    def _rebind(self, **kwargs):
+        params = {
+            "remote": REMOTE,
+            "org": ORG,
+            "repo": REPO,
+            "issue_number": ISSUE,
+            "branch_name": BRANCH,
+            "worktree_path": self.worktree,
+            "identity": IDENTITY,
+            "profile": PROFILE,
+            "lock_dir": self.lock_dir.name,
+            "now": self.now,
+        }
+        params.update(kwargs)
+        return issue_lock_store.rebind_legacy_lock(**params)
+
+    def test_rebind_mints_a_session_and_a_genuine_first_heartbeat(self):
+        self.write_lock(
+            lifecycle=None,
+            created_delta=timedelta(hours=3),
+            heartbeat_delta=timedelta(hours=3),
+            expires_delta=timedelta(hours=1),
+            generation=2,
+        )
+        result = self._rebind()
+        self.assertTrue(result["success"], result)
+        self.assertTrue(result["task_session_id"])
+        self.assertEqual(result["lock_generation"], 3)
+
+        written = issue_lock_store.read_lock_file(self._path())
+        lease = written["work_lease"]
+        self.assertEqual(
+            lease["lifecycle_version"], lease_policy.LIFECYCLE_HEARTBEAT_V1
+        )
+        self.assertEqual(lease["last_heartbeat_at"], _ts(self.now))
+        self.assertEqual(lease["expires_at"], _ts(self.now + timedelta(minutes=10)))
+        self.assertFalse(issue_lock_store.is_legacy_lease(written))
+        # The original claim is preserved for audit rather than overwritten.
+        origin = written["legacy_rebind"]["legacy_origin"]
+        self.assertTrue(origin["created_at"])
+        self.assertEqual(origin["lifecycle"], lease_policy.LIFECYCLE_LEGACY)
+
+    def test_rebound_lock_can_then_heartbeat(self):
+        self.write_lock(
+            lifecycle=None,
+            created_delta=timedelta(hours=3),
+            heartbeat_delta=timedelta(hours=3),
+            expires_delta=timedelta(hours=1),
+        )
+        rebound = self._rebind()
+        beat = issue_lock_store.heartbeat_session_lock(
+            remote=REMOTE,
+            org=ORG,
+            repo=REPO,
+            issue_number=ISSUE,
+            branch_name=BRANCH,
+            worktree_path=self.worktree,
+            identity=IDENTITY,
+            profile=PROFILE,
+            task_session_id=rebound["task_session_id"],
+            lock_dir=self.lock_dir.name,
+            now=self.now + timedelta(minutes=1),
+        )
+        self.assertTrue(beat["success"], beat)
+
+    def test_rebind_refuses_a_foreign_owner(self):
+        self.write_lock(lifecycle=None, expires_delta=timedelta(hours=1))
+        result = self._rebind(identity="someone-else")
+        self.assertFalse(result["success"])
+
+    def test_rebind_refuses_a_lock_already_on_the_lifecycle(self):
+        self.write_lock()
+        result = self._rebind()
+        self.assertFalse(result["success"])
+        self.assertFalse(result["legacy_lease"])
+
+    def test_rebind_is_not_a_recovery_path_for_a_lapsed_legacy_lease(self):
+        """An expired legacy lease belongs to #760 renewal or #601 reclaim."""
+        self.write_lock(
+            lifecycle=None,
+            created_delta=timedelta(hours=5),
+            heartbeat_delta=timedelta(hours=5),
+            expires_delta=timedelta(hours=-1),
+        )
+        result = self._rebind()
+        self.assertFalse(result["success"])
+        self.assertIn("not a recovery path", " ".join(result["reasons"]))
+
+
+if __name__ == "__main__":
+    unittest.main()
@@ -1,244 +0,0 @@
-"""#855 AC4: an expired reviewer lease must not indefinitely protect an
-already-merged branch when no live claimant exists.
-
-Two layers are covered:
-
-* ``branch_cleanup_guard.assess_expired_reviewer_lease_reclaim`` — the pure,
-  fail-closed reclaim decision. Every condition must be provably satisfied or
-  the lease keeps protecting the branch.
-* ``gitea_mcp_server._collect_branch_ownership_records`` — the wiring that
-  supplies authoritative evidence (PR merged state, owner-process liveness,
-  competing ownership) to that decision, and flips an expired reviewer lease
-  to reclaimable only under the full policy.
-
-All inputs are fabricated; no real repository, lease, or credential is used.
-"""
-
-import importlib
-import unittest
-from unittest.mock import patch
-
-import branch_cleanup_guard
-
-mcp_server = importlib.import_module("gitea_mcp_server")
-
-FAKE_AUTH = "token fake"
-REMOTE = "prgs"
-ORG = "Scaled-Tech-Consulting"
-REPO = "Gitea-Tools"
-HOST = "gitea.prgs.cc"
-BRANCH = "feat/issue-638-webui-app-shell-phase1"
-PR_NUMBER = 818
-
-
-class TestAssessExpiredReviewerLeaseReclaim(unittest.TestCase):
-    """Pure fail-closed reclaim decision (#855 AC4)."""
-
-    def _call(self, **overrides):
-        base = dict(
-            role="reviewer",
-            status="expired",
-            pr_merged=True,
-            owner_pid_alive=False,
-            competing_active_claimant=False,
-        )
-        base.update(overrides)
-        return branch_cleanup_guard.assess_expired_reviewer_lease_reclaim(**base)
-
-    def test_full_policy_satisfied_allows_reclaim(self):
-        out = self._call()
-        self.assertTrue(out["reclaim_allowed"])
-        self.assertEqual(out["reasons"], [])
-        self.assertEqual(out["decision"], "reclaim_expired_reviewer_lease")
-
-    def test_stale_dead_process_reviewer_also_reclaimable(self):
-        out = self._call(status="stale_dead_process")
-        self.assertTrue(out["reclaim_allowed"])
-
-    def test_non_reviewer_role_never_reclaims(self):
-        for role in ("author", "merger", "controller", "reconciler", "unknown"):
-            with self.subTest(role=role):
-                out = self._call(role=role)
-                self.assertFalse(out["reclaim_allowed"])
-                self.assertTrue(out["reasons"])
-                self.assertEqual(out["decision"], "keep_protecting")
-
-    def test_active_status_never_reclaims(self):
-        out = self._call(status="active")
-        self.assertFalse(out["reclaim_allowed"])
-
-    def test_pr_not_merged_blocks_reclaim(self):
-        out = self._call(pr_merged=False)
-        self.assertFalse(out["reclaim_allowed"])
-
-    def test_pr_merged_unknown_fails_closed(self):
-        out = self._call(pr_merged=None)
-        self.assertFalse(out["reclaim_allowed"])
-
-    def test_owner_process_alive_blocks_reclaim(self):
-        out = self._call(owner_pid_alive=True)
-        self.assertFalse(out["reclaim_allowed"])
-
-    def test_owner_liveness_unknown_fails_closed(self):
-        out = self._call(owner_pid_alive=None)
-        self.assertFalse(out["reclaim_allowed"])
-
-    def test_competing_active_claimant_blocks_reclaim(self):
-        out = self._call(competing_active_claimant=True)
-        self.assertFalse(out["reclaim_allowed"])
-
-    def test_competing_claimant_unknown_fails_closed(self):
-        out = self._call(competing_active_claimant=None)
-        self.assertFalse(out["reclaim_allowed"])
-
-    def test_reasons_never_leak_secrets(self):
-        out = self._call(role="author")
-        blob = " ".join(out["reasons"]).lower()
-        self.assertNotIn("token", blob)
-        self.assertNotIn("password", blob)
-
-
-class _FakeLease(dict):
-    pass
-
-
-class TestCollectorExpiredReviewerReclaimWiring(unittest.TestCase):
-    """`_collect_branch_ownership_records` supplies authoritative evidence and
-    flips an expired reviewer lease to reclaimable only under the full policy."""
-
-    def _run(
-        self,
-        *,
-        lease_role="reviewer",
-        lease_freshness="stale_dead_process",
-        owner_pid_alive=False,
-        pr_merged=True,
-        extra_leases=None,
-        worktree_on_branch=False,
-    ):
-        lease = _FakeLease(
-            role=lease_role,
-            work_kind="pr",
-            work_number=PR_NUMBER,
-            branch=BRANCH,
-            status="active",
-            owner_pid=999999,
-            remote=REMOTE,
-            org=ORG,
-            repo=REPO,
-            host=HOST,
-            freshness={
-                "freshness": lease_freshness,
-                "owner_pid": 999999,
-                "owner_pid_alive": owner_pid_alive,
-                "expired_by_time": lease_freshness == "expired",
-            },
-        )
-        leases = [lease] + list(extra_leases or [])
-
-        pr_payload = {
-            "number": PR_NUMBER,
-            "merged": pr_merged,
-            "merged_at": "2026-07-23T00:00:00Z" if pr_merged else None,
-            "head": {"ref": BRANCH},
-        }
-
-        def fake_api_request(method, url, *a, **k):
-            if method == "GET" and f"/pulls/{PR_NUMBER}" in url:
-                return pr_payload
-            raise AssertionError(f"unexpected api_request {method} {url}")
-
-        wt_entries = []
-        if worktree_on_branch:
-            wt_entries = [{"branch": BRANCH, "path": f"/x/branches/{BRANCH}"}]
-
-        with patch.object(
-            mcp_server.lease_lifecycle,
-            "list_active_leases",
-            return_value={"leases": leases},
-        ), patch.object(
-            mcp_server.control_plane_db, "get_db", return_value=object(), create=True
-        ), patch.object(
-            mcp_server.issue_lock_store, "iter_lock_files", return_value=[]
-        ), patch.object(
-            mcp_server.worktree_cleanup_audit,
-            "list_worktrees",
-            return_value=wt_entries,
-        ), patch.object(
-            mcp_server, "api_get_all", return_value=[]
-        ), patch.object(
-            mcp_server, "api_request", side_effect=fake_api_request
-        ):
-            return mcp_server._collect_branch_ownership_records(
-                remote=REMOTE,
-                host=HOST,
-                org=ORG,
-                repo=REPO,
-                branch=BRANCH,
-                pr_number=PR_NUMBER,
-                project_root="/x",
-                auth=FAKE_AUTH,
-                base_api="https://gitea.prgs.cc/api/v1/repos/x/y",
-            )
-
-    def _reviewer_records(self, bundle):
-        return [
-            rec
-            for rec in bundle["records"]
-            if rec.get("category")
-            == branch_cleanup_guard.OWNERSHIP_CATEGORY_REVIEWER_LEASE
-        ]
-
-    def test_merged_dead_uncontested_reviewer_lease_is_reclaimable(self):
-        bundle = self._run()
-        self.assertFalse(bundle["inventory_error"])
-        recs = self._reviewer_records(bundle)
-        self.assertEqual(len(recs), 1)
-        self.assertTrue(recs[0]["reclaim_allowed"])
-        # And the guard consequently does not block deletion on it.
-        ownership = branch_cleanup_guard.assess_active_branch_ownership(
-            remote=REMOTE, org=ORG, repo=REPO, branch=BRANCH, host=HOST,
-            records=bundle["records"],
-        )
-        self.assertFalse(ownership["block"])
-
-    def test_unmerged_pr_keeps_reviewer_lease_protective(self):
-        bundle = self._run(pr_merged=False)
-        recs = self._reviewer_records(bundle)
-        self.assertEqual(len(recs), 1)
-        self.assertFalse(recs[0]["reclaim_allowed"])
-        ownership = branch_cleanup_guard.assess_active_branch_ownership(
-            remote=REMOTE, org=ORG, repo=REPO, branch=BRANCH, host=HOST,
-            records=bundle["records"],
-        )
-        self.assertTrue(ownership["block"])
-
-    def test_owner_process_alive_keeps_reviewer_lease_protective(self):
-        bundle = self._run(owner_pid_alive=True, lease_freshness="expired")
-        recs = self._reviewer_records(bundle)
-        self.assertFalse(recs[0]["reclaim_allowed"])
-
-    def test_competing_worktree_binding_keeps_reviewer_lease_protective(self):
-        bundle = self._run(worktree_on_branch=True)
-        recs = self._reviewer_records(bundle)
-        self.assertFalse(recs[0]["reclaim_allowed"])
-        ownership = branch_cleanup_guard.assess_active_branch_ownership(
-            remote=REMOTE, org=ORG, repo=REPO, branch=BRANCH, host=HOST,
-            records=bundle["records"],
-        )
-        self.assertTrue(ownership["block"])
-
-    def test_expired_author_lease_never_reclaimed_by_reviewer_policy(self):
-        bundle = self._run(lease_role="author")
-        author_recs = [
-            rec
-            for rec in bundle["records"]
-            if rec.get("category")
-            == branch_cleanup_guard.OWNERSHIP_CATEGORY_AUTHOR_LEASE
-        ]
-        self.assertEqual(len(author_recs), 1)
-        self.assertFalse(author_recs[0]["reclaim_allowed"])
-
-
-if __name__ == "__main__":
-    unittest.main()
@@ -1,551 +0,0 @@
-"""Merged-PR awareness for the worktree cleanup audit (#858).
-
-Before #858 an ``issue_work`` worktree could never leave ``active_issue_work``:
-the audit had no PR linkage at all (``pr_number`` was structurally ``None``)
-and its only route to ``clean_stale_removable`` was a TTL derived from a
-``last_used_at`` that nothing ever populated. A merged, clean, unprotected
-worktree was therefore reported as active work forever, disagreeing with the
-PR-scoped reconciler.
-
-These tests use fabricated temporary repositories and synthetic PR records
-only. Nothing here removes a worktree or deletes a branch.
-"""
-
-import os
-import subprocess
-import sys
-import tempfile
-import unittest
-from unittest.mock import patch
-
-sys.path.insert(0, str(__import__("pathlib").Path(__file__).resolve().parent.parent))
-
-import merged_cleanup_reconcile as mcr  # noqa: E402
-import worktree_cleanup_audit as wca  # noqa: E402
-
-
-MERGED_BRANCH = "feat/issue-777-timeline"
-MERGED_PATH = "/repo/branches/issue-777-timeline"
-HEAD_SHA = "a" * 40
-
-
-def _pr(number, branch, *, merged=True, sha=HEAD_SHA, state=None):
-    """Synthetic Gitea PR payload."""
-    return {
-        "number": number,
-        "head": {"ref": branch, "sha": sha},
-        "merged_at": "2026-07-24T01:00:00Z" if merged else None,
-        "state": state or ("closed" if merged else "open"),
-    }
-
-
-def _porcelain(*entries):
-    out = []
-    for path, branch, sha in entries:
-        out.append(f"worktree {path}")
-        out.append(f"HEAD {sha}")
-        if branch is None:
-            out.append("detached")
-        else:
-            out.append(f"branch refs/heads/{branch}")
-        out.append("")
-    return "\n".join(out)
-
-
-class _AuditHarness(unittest.TestCase):
-    """Runs audit_branches_directory over a fabricated worktree listing."""
-
-    PORCELAIN = _porcelain(
-        ("/repo", "master", "f" * 40),
-        (MERGED_PATH, MERGED_BRANCH, HEAD_SHA),
-    )
-
-    def run_audit(self, *, dirty_paths=(), contained=True, **kwargs):
-        def fake_dirty(path):
-            if path in dirty_paths:
-                return {"exists": True, "dirty": True, "dirty_files": [" M x.py"]}
-            return {"exists": True, "dirty": False, "dirty_files": []}
-
-        with patch.object(
-            wca, "list_worktrees",
-            return_value=wca.parse_worktree_porcelain(self.PORCELAIN),
-        ), patch.object(
-            wca, "read_worktree_dirty", side_effect=fake_dirty
-        ), patch.object(
-            wca, "git_worktree_list", return_value="(mocked)"
-        ), patch.object(
-            wca, "is_head_ancestor_of_ref", return_value=contained
-        ):
-            report = wca.audit_branches_directory("/repo", **kwargs)
-        return {wt["path"]: wt for wt in report["worktrees"]}, report
-
-    def merged_audit(self, **kwargs):
-        kwargs.setdefault("pr_index", wca.build_pr_index([_pr(849, MERGED_BRANCH)]))
-        kwargs.setdefault("master_ref", "prgs/master")
-        return self.run_audit(**kwargs)
-
-
-class TestMergedWorktreeBecomesRemovable(_AuditHarness):
-    def test_clean_merged_issue_worktree_is_linked_and_removable(self):
-        by_path, report = self.merged_audit()
-        entry = by_path[MERGED_PATH]
-
-        self.assertEqual(entry["classification"], wca.CLASS_CLEAN_STALE_REMOVABLE)
-        self.assertTrue(entry["removable"])
-        self.assertEqual(entry["merged_pr_linkage"]["status"], wca.LINKAGE_MERGED)
-        self.assertEqual(entry["merged_pr_cleanup"]["block_reasons"], [])
-        self.assertIn(MERGED_PATH, [c["path"] for c in report["removable_candidates"]])
-
-    def test_pr_number_populated_from_authoritative_linkage(self):
-        by_path, _ = self.merged_audit()
-        self.assertEqual(by_path[MERGED_PATH]["pr_number"], 849)
-
-    def test_regression_without_pr_evidence_stays_active_issue_work(self):
-        """The pre-#858 behaviour, still correct when no PR state is supplied."""
-        by_path, _ = self.run_audit()
-        entry = by_path[MERGED_PATH]
-        self.assertEqual(entry["classification"], wca.CLASS_ACTIVE_ISSUE_WORK)
-        self.assertFalse(entry["removable"])
-        self.assertIsNone(entry["pr_number"])
-
-
-class TestProtectiveSignalsSurvive(_AuditHarness):
-    def test_open_pr_worktree_is_not_removable(self):
-        index = wca.build_pr_index([_pr(900, MERGED_BRANCH, merged=False)])
-        by_path, _ = self.run_audit(
-            pr_index=index,
-            master_ref="prgs/master",
-            open_pr_branches={MERGED_BRANCH},
-        )
-        entry = by_path[MERGED_PATH]
-        self.assertEqual(entry["classification"], wca.CLASS_ACTIVE_OPEN_PR)
-        self.assertFalse(entry["removable"])
-        # linkage still reports the owning PR, it just is not merge proof
-        self.assertEqual(entry["merged_pr_linkage"]["status"], wca.LINKAGE_OPEN)
-        self.assertEqual(entry["pr_number"], 900)
-
-    def test_dirty_tracked_worktree_is_not_removable(self):
-        by_path, _ = self.merged_audit(dirty_paths=(MERGED_PATH,))
-        entry = by_path[MERGED_PATH]
-        self.assertEqual(entry["classification"], wca.CLASS_DIRTY_LOCAL)
-        self.assertFalse(entry["removable"])
-        self.assertIn(
-            "worktree has uncommitted changes",
-            entry["merged_pr_cleanup"]["block_reasons"],
-        )
-
-    def test_untracked_only_worktree_is_not_removable(self):
-        """``git status --porcelain`` reports untracked files as dirty too."""
-        def untracked(path):
-            if path == MERGED_PATH:
-                return {"exists": True, "dirty": True, "dirty_files": ["?? scratch.txt"]}
-            return {"exists": True, "dirty": False, "dirty_files": []}
-
-        with patch.object(
-            wca, "list_worktrees",
-            return_value=wca.parse_worktree_porcelain(self.PORCELAIN),
-        ), patch.object(
-            wca, "read_worktree_dirty", side_effect=untracked
-        ), patch.object(
-            wca, "git_worktree_list", return_value="(mocked)"
-        ), patch.object(
-            wca, "is_head_ancestor_of_ref", return_value=True
-        ):
-            report = wca.audit_branches_directory(
-                "/repo",
-                pr_index=wca.build_pr_index([_pr(849, MERGED_BRANCH)]),
-                master_ref="prgs/master",
-            )
-        entry = {wt["path"]: wt for wt in report["worktrees"]}[MERGED_PATH]
-        self.assertEqual(entry["classification"], wca.CLASS_DIRTY_LOCAL)
-        self.assertFalse(entry["removable"])
-
-    def test_active_lease_by_issue_number_is_protective(self):
-        by_path, _ = self.merged_audit(leased_issue_numbers={777})
-        entry = by_path[MERGED_PATH]
-        self.assertTrue(entry["has_active_lease"])
-        self.assertEqual(entry["classification"], wca.CLASS_ACTIVE_ISSUE_WORK)
-        self.assertFalse(entry["removable"])
-
-    def test_active_lease_by_branch_is_protective(self):
-        by_path, _ = self.merged_audit(leased_branches={MERGED_BRANCH})
-        entry = by_path[MERGED_PATH]
-        self.assertTrue(entry["has_active_lease"])
-        self.assertFalse(entry["removable"])
-
-    def test_active_issue_lock_is_protective(self):
-        by_path, _ = self.merged_audit(active_issue_branches={MERGED_BRANCH})
-        entry = by_path[MERGED_PATH]
-        self.assertTrue(entry["has_active_issue_lock"])
-        self.assertEqual(entry["classification"], wca.CLASS_ACTIVE_ISSUE_WORK)
-        self.assertFalse(entry["removable"])
-
-    def test_live_session_worktree_is_protective(self):
-        by_path, _ = self.merged_audit(live_session_paths={MERGED_PATH})
-        entry = by_path[MERGED_PATH]
-        self.assertTrue(entry["has_live_session"])
-        self.assertEqual(entry["classification"], wca.CLASS_ACTIVE_ISSUE_WORK)
-        self.assertFalse(entry["removable"])
-
-    def test_head_not_contained_in_master_is_not_removable(self):
-        by_path, _ = self.merged_audit(contained=False)
-        entry = by_path[MERGED_PATH]
-        self.assertEqual(entry["classification"], wca.CLASS_ACTIVE_ISSUE_WORK)
-        self.assertFalse(entry["removable"])
-        self.assertIn(
-            "worktree head is not contained in authoritative master "
-            "(unmerged commits remain)",
-            entry["merged_pr_cleanup"]["block_reasons"],
-        )
-
-    def test_unknown_containment_fails_closed(self):
-        by_path, _ = self.merged_audit(contained=None)
-        entry = by_path[MERGED_PATH]
-        self.assertFalse(entry["removable"])
-        self.assertIn(
-            "containment of the worktree head in master is unknown",
-            entry["merged_pr_cleanup"]["block_reasons"],
-        )
-
-    def test_missing_master_ref_fails_closed(self):
-        by_path, _ = self.run_audit(
-            pr_index=wca.build_pr_index([_pr(849, MERGED_BRANCH)])
-        )
-        self.assertFalse(by_path[MERGED_PATH]["removable"])
-
-    def test_unmerged_owning_pr_is_not_removable(self):
-        index = wca.build_pr_index([_pr(901, MERGED_BRANCH, merged=False)])
-        by_path, _ = self.run_audit(pr_index=index, master_ref="prgs/master")
-        entry = by_path[MERGED_PATH]
-        self.assertFalse(entry["removable"])
-        self.assertIn(
-            "owning PR #901 is not merged",
-            entry["merged_pr_cleanup"]["block_reasons"],
-        )
-
-    def test_control_checkout_is_never_removable(self):
-        by_path, _ = self.merged_audit()
-        control = by_path["/repo"]
-        self.assertTrue(control["is_protected"])
-        self.assertEqual(control["classification"], wca.CLASS_UNSAFE_UNKNOWN)
-        self.assertFalse(control["removable"])
-
-    def test_control_checkout_not_removable_even_if_linked_and_merged(self):
-        """A merged PR on the control checkout must not unlock removal."""
-        porcelain = _porcelain(("/repo", MERGED_BRANCH, HEAD_SHA))
-        with patch.object(
-            wca, "list_worktrees", return_value=wca.parse_worktree_porcelain(porcelain)
-        ), patch.object(
-            wca, "read_worktree_dirty",
-            return_value={"exists": True, "dirty": False, "dirty_files": []},
-        ), patch.object(
-            wca, "git_worktree_list", return_value="(mocked)"
-        ), patch.object(
-            wca, "is_head_ancestor_of_ref", return_value=True
-        ):
-            report = wca.audit_branches_directory(
-                "/repo",
-                pr_index=wca.build_pr_index([_pr(849, MERGED_BRANCH)]),
-                master_ref="prgs/master",
-            )
-        entry = report["worktrees"][0]
-        self.assertEqual(entry["classification"], wca.CLASS_UNSAFE_UNKNOWN)
-        self.assertFalse(entry["removable"])
-
-
-class TestAmbiguousLinkageFailsClosed(_AuditHarness):
-    def test_competing_prs_on_one_branch_fail_closed(self):
-        index = wca.build_pr_index(
-            [_pr(849, MERGED_BRANCH), _pr(860, MERGED_BRANCH)]
-        )
-        by_path, _ = self.run_audit(pr_index=index, master_ref="prgs/master")
-        entry = by_path[MERGED_PATH]
-        self.assertEqual(entry["merged_pr_linkage"]["status"], wca.LINKAGE_AMBIGUOUS)
-        self.assertIsNone(entry["pr_number"])
-        self.assertEqual(entry["classification"], wca.CLASS_ACTIVE_ISSUE_WORK)
-        self.assertFalse(entry["removable"])
-
-    def test_merged_plus_open_pr_on_one_branch_fails_closed(self):
-        index = wca.build_pr_index(
-            [_pr(849, MERGED_BRANCH), _pr(861, MERGED_BRANCH, merged=False)]
-        )
-        by_path, _ = self.run_audit(pr_index=index, master_ref="prgs/master")
-        entry = by_path[MERGED_PATH]
-        self.assertEqual(entry["merged_pr_linkage"]["status"], wca.LINKAGE_AMBIGUOUS)
-        self.assertFalse(entry["removable"])
-
-    def test_no_owning_pr_fails_closed(self):
-        by_path, _ = self.run_audit(
-            pr_index=wca.build_pr_index([_pr(849, "feat/other-branch")]),
-            master_ref="prgs/master",
-        )
-        entry = by_path[MERGED_PATH]
-        self.assertEqual(entry["merged_pr_linkage"]["status"], wca.LINKAGE_NONE)
-        self.assertFalse(entry["removable"])
-
-    def test_malformed_pr_records_are_dropped_not_guessed(self):
-        index = wca.build_pr_index(
-            [
-                {"number": None, "head": {"ref": MERGED_BRANCH}},
-                {"number": 5, "head": {}},
-                {"number": "not-an-int", "head": {"ref": MERGED_BRANCH}},
-            ]
-        )
-        self.assertEqual(index, {})
-        self.assertEqual(
-            wca.resolve_owning_pr(branch=MERGED_BRANCH, pr_index=index)["status"],
-            wca.LINKAGE_NONE,
-        )
-
-    def test_detached_worktree_has_no_branch_linkage(self):
-        self.assertEqual(
-            wca.resolve_owning_pr(branch=None, pr_index={})["status"],
-            wca.LINKAGE_UNKNOWN,
-        )
-
-
-class TestUnrelatedClassificationsUnchanged(unittest.TestCase):
-    """Non-issue_work worktrees keep their pre-#858 classifications."""
-
-    PORCELAIN = _porcelain(
-        ("/repo", "master", "f" * 40),
-        ("/repo/branches/review-pr42", "review-pr42", "2" * 40),
-        ("/repo/branches/baseline-master-x", "baseline-master-x", "3" * 40),
-        ("/repo/branches/conflict-fix-pr50", "conflict-fix-pr50", "4" * 40),
-        ("/repo/branches/review-pr99", None, "5" * 40),
-    )
-
-    def _audit(self, **kwargs):
-        with patch.object(
-            wca, "list_worktrees",
-            return_value=wca.parse_worktree_porcelain(self.PORCELAIN),
-        ), patch.object(
-            wca, "read_worktree_dirty",
-            return_value={"exists": True, "dirty": False, "dirty_files": []},
-        ), patch.object(
-            wca, "git_worktree_list", return_value="(mocked)"
-        ), patch.object(
-            wca, "is_head_ancestor_of_ref", return_value=True
-        ):
-            report = wca.audit_branches_directory("/repo", **kwargs)
-        return {wt["path"]: wt for wt in report["worktrees"]}
-
-    def test_classifications_identical_with_and_without_pr_evidence(self):
-        without = self._audit()
-        with_evidence = self._audit(
-            pr_index=wca.build_pr_index([_pr(849, MERGED_BRANCH)]),
-            master_ref="prgs/master",
-        )
-        self.assertEqual(
-            {p: e["classification"] for p, e in without.items()},
-            {p: e["classification"] for p, e in with_evidence.items()},
-        )
-
-    def test_lease_on_issue_does_not_capture_similarly_named_scratch_trees(self):
-        """A lease on issue 777 protects issue work, not baseline/review trees."""
-        porcelain = _porcelain(
-            ("/repo/branches/baseline-master-issue-777", "baseline-issue-777", "7" * 40),
-            ("/repo/branches/issue-777-timeline", MERGED_BRANCH, HEAD_SHA),
-        )
-        with patch.object(
-            wca, "list_worktrees", return_value=wca.parse_worktree_porcelain(porcelain)
-        ), patch.object(
-            wca, "read_worktree_dirty",
-            return_value={"exists": True, "dirty": False, "dirty_files": []},
-        ), patch.object(
-            wca, "git_worktree_list", return_value="(mocked)"
-        ), patch.object(
-            wca, "is_head_ancestor_of_ref", return_value=True
-        ):
-            report = wca.audit_branches_directory(
-                "/repo",
-                pr_index=wca.build_pr_index([_pr(849, MERGED_BRANCH)]),
-                master_ref="prgs/master",
-                leased_issue_numbers={777},
-            )
-        by_path = {wt["path"]: wt for wt in report["worktrees"]}
-
-        baseline = by_path["/repo/branches/baseline-master-issue-777"]
-        self.assertFalse(baseline["has_active_lease"])
-        self.assertEqual(baseline["classification"], wca.CLASS_CLEAN_STALE_REMOVABLE)
-
-        issue_work = by_path["/repo/branches/issue-777-timeline"]
-        self.assertTrue(issue_work["has_active_lease"])
-        self.assertFalse(issue_work["removable"])
-
-    def test_review_and_baseline_still_removable(self):
-        by_path = self._audit(
-            pr_index=wca.build_pr_index([]), master_ref="prgs/master"
-        )
-        self.assertEqual(
-            by_path["/repo/branches/review-pr42"]["classification"],
-            wca.CLASS_CLEAN_STALE_REMOVABLE,
-        )
-        self.assertEqual(
-            by_path["/repo/branches/baseline-master-x"]["classification"],
-            wca.CLASS_CLEAN_STALE_REMOVABLE,
-        )
-        self.assertEqual(
-            by_path["/repo/branches/review-pr99"]["classification"],
-            wca.CLASS_DETACHED_REVIEW_LEFTOVER,
-        )
-
-    def test_conflict_fix_ttl_behaviour_unchanged(self):
-        """conflict_fix still needs only TTL expiry; #858 did not touch it."""
-        self.assertEqual(
-            wca.classify_worktree(
-                workflow_type=wca.WORKFLOW_CONFLICT_FIX,
-                is_dirty=False,
-                ttl_expired=True,
-            ),
-            wca.CLASS_CLEAN_STALE_REMOVABLE,
-        )
-        self.assertEqual(
-            wca.classify_worktree(
-                workflow_type=wca.WORKFLOW_CONFLICT_FIX,
-                is_dirty=False,
-                ttl_expired=False,
-            ),
-            wca.CLASS_ACTIVE_ISSUE_WORK,
-        )
-
-    def test_issue_work_ttl_alone_no_longer_grants_removal(self):
-        """Age is not landing proof: TTL alone must not reclaim issue work."""
-        self.assertEqual(
-            wca.classify_worktree(
-                workflow_type=wca.WORKFLOW_ISSUE_WORK,
-                is_dirty=False,
-                ttl_expired=True,
-            ),
-            wca.CLASS_ACTIVE_ISSUE_WORK,
-        )
-
-
-class TestAssessorPerformsNoDeletion(_AuditHarness):
-    def test_audit_never_removes_a_worktree(self):
-        with patch.object(wca, "remove_worktree") as removal:
-            self.merged_audit()
-        removal.assert_not_called()
-
-    def test_audit_shells_out_to_no_destructive_git_command(self):
-        seen = []
-        real_run = subprocess.run
-
-        def recording_run(cmd, *args, **kwargs):
-            seen.append(cmd)
-            return real_run(["true"], *args, **kwargs)
-
-        with patch.object(subprocess, "run", side_effect=recording_run):
-            wca.audit_branches_directory("/nonexistent-repo-for-audit")
-
-        joined = [" ".join(c) if isinstance(c, list) else str(c) for c in seen]
-        for cmd in joined:
-            self.assertNotIn("worktree remove", cmd)
-            self.assertNotIn("branch -D", cmd)
-            self.assertNotIn("push", cmd)
-
-
-class TestAgreementWithPrScopedReconciler(unittest.TestCase):
-    """The audit and merged_cleanup_reconcile must agree on identical input.
-
-    Uses a real throwaway git repository so containment is computed by git
-    rather than asserted. Nothing outside the temporary directory is touched.
-    """
-
-    def _git(self, *args):
-        subprocess.run(
-            ["git", "-C", self.root, *args],
-            check=True,
-            capture_output=True,
-            text=True,
-        )
-
-    def setUp(self):
-        self._tmp = tempfile.TemporaryDirectory()
-        self.root = os.path.realpath(self._tmp.name)
-        self._git("init", "-b", "master", ".")
-        self._git("config", "user.email", "[email protected]")
-        self._git("config", "user.name", "Test")
-        with open(os.path.join(self.root, "seed.txt"), "w") as fh:
-            fh.write("seed\n")
-        self._git("add", "seed.txt")
-        self._git("commit", "-m", "seed")
-
-        self.branch = "feat/issue-777-timeline"
-        self._git("checkout", "-b", self.branch)
-        with open(os.path.join(self.root, "feature.txt"), "w") as fh:
-            fh.write("feature\n")
-        self._git("add", "feature.txt")
-        self._git("commit", "-m", "feature")
-        self.head_sha = subprocess.run(
-            ["git", "-C", self.root, "rev-parse", "HEAD"],
-            capture_output=True, text=True, check=True,
-        ).stdout.strip()
-        self._git("checkout", "master")
-        self._git("merge", "--no-ff", "-m", "merge feature", self.branch)
-
-        self.worktree = os.path.join(self.root, "branches", "issue-777-timeline")
-        self._git("worktree", "add", self.worktree, self.branch)
-
-    def tearDown(self):
-        self._tmp.cleanup()
-
-    def _pr_index(self):
-        return wca.build_pr_index(
-            [
-                {
-                    "number": 849,
-                    "head": {"ref": self.branch, "sha": self.head_sha},
-                    "merged_at": "2026-07-24T01:00:00Z",
-                }
-            ]
-        )
-
-    def _audit_entry(self):
-        report = wca.audit_branches_directory(
-            self.root, pr_index=self._pr_index(), master_ref="master"
-        )
-        return next(wt for wt in report["worktrees"] if wt["path"] == self.worktree)
-
-    def _reconciler_entry(self):
-        return mcr.assess_local_worktree_cleanup(
-            pr_number=849,
-            head_branch=self.branch,
-            merged=True,
-            worktree_state=mcr.resolve_cleanup_worktree_state(
-                project_root=self.root,
-                head_branch=self.branch,
-                issue_number=777,
-                pr_head_sha=self.head_sha,
-                target_ref="master",
-            ),
-            active_lock=False,
-        )
-
-    def test_both_assessors_agree_the_worktree_is_safe(self):
-        audit_entry = self._audit_entry()
-        reconciler = self._reconciler_entry()
-
-        self.assertTrue(reconciler["safe_to_remove_worktree"], reconciler)
-        self.assertTrue(audit_entry["removable"], audit_entry)
-        self.assertEqual(audit_entry["pr_number"], reconciler["pr_number"])
-        self.assertEqual(audit_entry["merged_pr_cleanup"]["block_reasons"], [])
-        self.assertEqual(reconciler["block_reasons"], [])
-
-    def test_both_assessors_agree_a_dirty_worktree_is_unsafe(self):
-        with open(os.path.join(self.worktree, "feature.txt"), "a") as fh:
-            fh.write("local edit\n")
-
-        audit_entry = self._audit_entry()
-        reconciler = self._reconciler_entry()
-
-        self.assertFalse(audit_entry["removable"])
-        self.assertFalse(reconciler["safe_to_remove_worktree"])
-
-    def test_worktree_still_present_after_audit(self):
-        self._audit_entry()
-        self.assertTrue(os.path.isdir(self.worktree))
-
-
-if __name__ == "__main__":
-    unittest.main()
@@ -1,630 +0,0 @@
-"""Durable linked-issue lock head refresh + merge-sync dead-session recovery (#871).
-
-``gitea_update_pr_branch_by_merge`` advances a PR's *remote* head but historically
-never advanced the linked durable issue lock's recorded head. After the owning
-session died the drifted lock became unrecoverable and no further synchronization
-was possible (PR #866 / issue #855).
-
-Two halves are covered:
-
-* the write-side refresh (``issue_lock_store.assess/apply_durable_lock_head_refresh``)
-  that records the new synced head under compare-and-swap with read-after-write; and
-* the read-side recovery relation (``issue_lock_recovery`` +
-  ``issue_lock_worktree.read_merge_sync_provenance``) that lets a dead-session lock
-  whose recorded head is a merge-sync *ancestor* of the live PR head be recovered —
-  and nothing else.
-"""
-
-from __future__ import annotations
-
-import os
-import subprocess
-import sys
-import tempfile
-import unittest
-from datetime import datetime, timedelta, timezone
-from pathlib import Path
-
-sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
-
-import issue_lock_recovery  # noqa: E402
-import issue_lock_store  # noqa: E402
-import issue_lock_worktree  # noqa: E402
-
-ISSUE = 8710
-PR_NUMBER = 8711
-BRANCH = f"fix/issue-{ISSUE}-durable-lock-head-refresh"
-IDENTITY = "example-user"
-PROFILE = "example-author"
-OLD = "a" * 40
-NEW1 = "b" * 40
-NEW2 = "c" * 40
-BASE = "d" * 40
-REMOTE = "prgs"
-ORG = "ExampleOrg"
-REPO = "ExampleRepo"
-
-
-def dead_pid() -> int:
-    proc = subprocess.Popen([sys.executable, "-c", "pass"])
-    proc.wait()
-    return proc.pid
-
-
-def future_ts(hours: int = 4) -> str:
-    return (
-        (datetime.now(timezone.utc) + timedelta(hours=hours))
-        .isoformat()
-        .replace("+00:00", "Z")
-    )
-
-
-def _git(cwd, *args):
-    return subprocess.run(
-        ["git", "-C", cwd, *args],
-        capture_output=True,
-        text=True,
-        check=True,
-    )
-
-
-def _rev(cwd, ref="HEAD") -> str:
-    return _git(cwd, "rev-parse", ref).stdout.strip()
-
-
-def build_merge_sync_repo(tmp: str) -> dict:
-    """Build a repo where a feature branch was synced by merging master in.
-
-    Returns a dict with the prior (branch) head, the synced merge-commit head,
-    the master tip, plus a rebase-style linear descendant and an unrelated head.
-    """
-    _git(tmp, "init", "-q", "-b", "master")
-    _git(tmp, "config", "user.email", "[email protected]")
-    _git(tmp, "config", "user.name", "T")
-    Path(tmp, "base.txt").write_text("base\n")
-    _git(tmp, "add", "-A")
-    _git(tmp, "commit", "-q", "-m", "root")
-
-    # Feature branch cut from root, one commit — this is the PRIOR/recorded head.
-    _git(tmp, "checkout", "-q", "-b", BRANCH)
-    Path(tmp, "feature.txt").write_text("feature\n")
-    _git(tmp, "add", "-A")
-    _git(tmp, "commit", "-q", "-m", "feature work")
-    prior = _rev(tmp)
-
-    # Master advances (the base the sync will merge in).
-    _git(tmp, "checkout", "-q", "master")
-    Path(tmp, "base.txt").write_text("base\nmore\n")
-    _git(tmp, "add", "-A")
-    _git(tmp, "commit", "-q", "-m", "master advance")
-    master_tip = _rev(tmp)
-
-    # Sync: merge master INTO the feature branch → merge commit, first parent = prior.
-    _git(tmp, "checkout", "-q", BRANCH)
-    _git(tmp, "merge", "-q", "--no-ff", "-m", "Merge master into feature", "master")
-    synced = _rev(tmp)
-
-    # A plain linear descendant of prior (NOT a merge) — a rebase/extra-commit shape.
-    _git(tmp, "checkout", "-q", "-b", "linear-branch", prior)
-    Path(tmp, "extra.txt").write_text("extra\n")
-    _git(tmp, "add", "-A")
-    _git(tmp, "commit", "-q", "-m", "extra linear commit")
-    linear = _rev(tmp)
-
-    # An unrelated root (force-push / rewritten history shape).
-    unrelated_dir = tempfile.mkdtemp()
-    _git(unrelated_dir, "init", "-q", "-b", "x")
-    _git(unrelated_dir, "config", "user.email", "[email protected]")
-    _git(unrelated_dir, "config", "user.name", "T")
-    Path(unrelated_dir, "z.txt").write_text("z\n")
-    _git(unrelated_dir, "add", "-A")
-    _git(unrelated_dir, "commit", "-q", "-m", "unrelated")
-    unrelated = _rev(unrelated_dir)
-
-    # Leave the worktree checked out on the feature branch at the PRIOR head, as
-    # a dead author session that never advanced would have left it.
-    _git(tmp, "checkout", "-q", BRANCH)
-    _git(tmp, "reset", "-q", "--hard", prior)
-
-    return {
-        "prior": prior,
-        "master_tip": master_tip,
-        "synced": synced,
-        "linear": linear,
-        "unrelated": unrelated,
-    }
-
-
-# ─────────────────────────── write-side refresh ───────────────────────────
-
-
-class TestDurableLockHeadRefresh(unittest.TestCase):
-    def setUp(self):
-        self.lock_dir = tempfile.mkdtemp()
-        self.wt = tempfile.mkdtemp()
-        lock_data = {
-            "issue_number": ISSUE,
-            "branch_name": BRANCH,
-            "worktree_path": self.wt,
-            "remote": REMOTE,
-            "org": ORG,
-            "repo": REPO,
-            "claimant": {"username": IDENTITY, "profile": PROFILE},
-            "work_lease": {
-                "operation_type": issue_lock_store.AUTHOR_ISSUE_WORK_LEASE,
-                "issue_number": ISSUE,
-                "branch": BRANCH,
-                "worktree_path": self.wt,
-                "claimant": {"username": IDENTITY, "profile": PROFILE},
-                "expires_at": future_ts(),
-            },
-        }
-        issue_lock_store.bind_session_lock(lock_data, lock_dir=self.lock_dir)
-
-    def _apply(self, **over):
-        kw = dict(
-            remote=REMOTE, org=ORG, repo=REPO, issue_number=ISSUE,
-            branch_name=BRANCH, worktree_path=self.wt, pr_number=PR_NUMBER,
-            identity=IDENTITY, profile=PROFILE, current_pid=os.getpid(),
-            expected_old_head=OLD, new_head=NEW1, synced_at=future_ts(0),
-            base_head=BASE, lock_dir=self.lock_dir,
-        )
-        kw.update(over)
-        return issue_lock_store.apply_durable_lock_head_refresh(**kw)
-
-    def _load(self):
-        return issue_lock_store.load_issue_lock(
-            remote=REMOTE, org=ORG, repo=REPO, issue_number=ISSUE,
-            lock_dir=self.lock_dir,
-        )
-
-    def test_first_sync_updates_recorded_head(self):
-        """AC1: first base sync writes the resulting head to the durable lock."""
-        res = self._apply()
-        self.assertTrue(res["refreshed"], res["reasons"])
-        self.assertTrue(res["read_after_write_ok"])
-        self.assertEqual(self._load().get("synced_pr_head"), NEW1)
-
-    def test_second_sync_after_master_advance(self):
-        """AC2: a later master advance permits a second sanctioned sync."""
-        self.assertTrue(self._apply()["refreshed"])
-        res2 = self._apply(expected_old_head=NEW1, new_head=NEW2)
-        self.assertTrue(res2["refreshed"], res2["reasons"])
-        self.assertEqual(self._load().get("synced_pr_head"), NEW2)
-        history = self._load().get("branch_sync_history")
-        self.assertEqual(len(history), 2)
-        self.assertEqual(history[0]["last_synced_pr_head"], NEW1)
-        self.assertEqual(history[1]["prior_pr_head"], NEW1)
-
-    def test_cas_detects_concurrent_head_change(self):
-        """AC6: CAS refuses when the recorded synced head is not the old head."""
-        self.assertTrue(self._apply()["refreshed"])  # recorded head now NEW1
-        # A second sync claiming the old head is still OLD must fail closed.
-        res = self._apply(expected_old_head=OLD, new_head=NEW2)
-        self.assertFalse(res["refreshed"])
-        self.assertTrue(any("CAS" in r or "concurrent" in r for r in res["reasons"]))
-        self.assertEqual(self._load().get("synced_pr_head"), NEW1)
-
-    def test_wrong_issue_fails_closed(self):
-        res = self._apply(issue_number=999999)
-        self.assertFalse(res["refreshed"])
-
-    def test_wrong_branch_fails_closed(self):
-        res = self._apply(branch_name="fix/issue-8710-wrong")
-        self.assertFalse(res["refreshed"])
-
-    def test_wrong_repo_fails_closed(self):
-        res = self._apply(repo="OtherRepo")
-        self.assertFalse(res["refreshed"])
-
-    def test_wrong_identity_fails_closed(self):
-        res = self._apply(identity="intruder")
-        self.assertFalse(res["refreshed"])
-
-    def test_wrong_profile_fails_closed(self):
-        res = self._apply(profile="prgs-reviewer")
-        self.assertFalse(res["refreshed"])
-
-    def test_foreign_session_fails_closed(self):
-        """A refresh is not a recovery: the current process must own the lock."""
-        path = issue_lock_store.lock_file_path(
-            remote=REMOTE, org=ORG, repo=REPO, issue_number=ISSUE,
-            lock_dir=self.lock_dir,
-        )
-        rec = issue_lock_store.read_lock_file(path)
-        rec["session_pid"] = dead_pid()
-        rec["pid"] = rec["session_pid"]
-        issue_lock_store.save_lock_file(path, rec)
-        res = self._apply()
-        self.assertFalse(res["refreshed"])
-        self.assertTrue(any("current session" in r or "live owner" in r for r in res["reasons"]))
-
-    def test_new_equals_old_fails_closed(self):
-        res = self._apply(expected_old_head=OLD, new_head=OLD)
-        self.assertFalse(res["refreshed"])
-
-    def test_non_full_sha_fails_closed(self):
-        self.assertFalse(self._apply(new_head="deadbeef")["refreshed"])
-        self.assertFalse(self._apply(expected_old_head="xyz")["refreshed"])
-
-    def test_no_lock_fails_closed(self):
-        assessment = issue_lock_store.assess_durable_lock_head_refresh(
-            None, remote=REMOTE, org=ORG, repo=REPO, issue_number=ISSUE,
-            branch_name=BRANCH, worktree_path=self.wt, pr_number=PR_NUMBER,
-            identity=IDENTITY, profile=PROFILE, current_pid=os.getpid(),
-            expected_old_head=OLD, new_head=NEW1,
-        )
-        self.assertFalse(assessment["allowed"])
-
-
-# ─────────────────────── merge-sync provenance (real git) ───────────────────
-
-
-class TestMergeSyncProvenanceObservation(unittest.TestCase):
-    def setUp(self):
-        self.tmp = tempfile.mkdtemp()
-        self.shas = build_merge_sync_repo(self.tmp)
-
-    def test_merge_sync_is_recognized(self):
-        obs = issue_lock_worktree.read_merge_sync_provenance(
-            self.tmp, prior_head_sha=self.shas["prior"],
-            synced_head_sha=self.shas["synced"],
-        )
-        self.assertTrue(obs["is_merge_sync"], obs["reasons"])
-        self.assertTrue(obs["prior_is_ancestor"])
-        self.assertTrue(obs["synced_is_merge"])
-        self.assertTrue(obs["first_parent_reaches_prior"])
-
-    def test_linear_descendant_is_not_a_merge_sync(self):
-        """A plain non-merge descendant (rebase/extra commit) is not a sync."""
-        obs = issue_lock_worktree.read_merge_sync_provenance(
-            self.tmp, prior_head_sha=self.shas["prior"],
-            synced_head_sha=self.shas["linear"],
-        )
-        self.assertTrue(obs["probe_ok"])
-        self.assertFalse(obs["is_merge_sync"])
-        self.assertFalse(obs["synced_is_merge"])
-
-    def test_unrelated_history_fails_closed(self):
-        """A rewritten/force-pushed head where prior is unreachable fails closed."""
-        obs = issue_lock_worktree.read_merge_sync_provenance(
-            self.tmp, prior_head_sha=self.shas["prior"],
-            synced_head_sha=self.shas["unrelated"],
-        )
-        self.assertFalse(obs["is_merge_sync"])
-
-    def test_missing_args_fail_closed(self):
-        obs = issue_lock_worktree.read_merge_sync_provenance(
-            self.tmp, prior_head_sha=None, synced_head_sha=self.shas["synced"],
-        )
-        self.assertFalse(obs["is_merge_sync"])
-
-
-# ──────────────────── merge-sync dead-session recovery ──────────────────────
-
-
-def make_dead_lock(worktree, **over):
-    pid = dead_pid()
-    lock = {
-        "issue_number": ISSUE,
-        "branch_name": BRANCH,
-        "worktree_path": worktree,
-        "remote": REMOTE,
-        "org": ORG,
-        "repo": REPO,
-        "session_pid": pid,
-        "pid": pid,
-        "claimant": {"username": IDENTITY, "profile": PROFILE},
-        "work_lease": {
-            "operation_type": issue_lock_store.AUTHOR_ISSUE_WORK_LEASE,
-            "issue_number": ISSUE,
-            "branch": BRANCH,
-            "worktree_path": worktree,
-            "claimant": {"username": IDENTITY, "profile": PROFILE},
-            "expires_at": future_ts(),
-        },
-    }
-    lock.update(over)
-    return lock
-
-
-def sync_prov(prior, synced, **over):
-    d = {
-        "prior_head_sha": prior,
-        "synced_head_sha": synced,
-        "probe_ok": True,
-        "prior_present": True,
-        "synced_present": True,
-        "prior_is_ancestor": True,
-        "synced_is_merge": True,
-        "first_parent_reaches_prior": True,
-        "is_merge_sync": True,
-        "first_parent_sha": prior,
-        "parent_count": 2,
-        "proof": f"{synced} merged base into branch above {prior}",
-        "reasons": [],
-    }
-    d.update(over)
-    return d
-
-
-class TestMergeSyncRecovery(unittest.TestCase):
-    def setUp(self):
-        self.tmp = tempfile.mkdtemp()
-        self.shas = build_merge_sync_repo(self.tmp)
-        self.prior = self.shas["prior"]
-        self.synced = self.shas["synced"]
-
-    def _assess(self, **over):
-        lock = over.pop("_lock", None) or make_dead_lock(self.tmp)
-        kw = dict(
-            issue_number=ISSUE, branch_name=BRANCH, worktree_path=self.tmp,
-            remote=REMOTE, org=ORG, repo=REPO, identity=IDENTITY, profile=PROFILE,
-            current_branch=BRANCH, porcelain_status="",
-            head_sha=self.prior, remote_head_sha=self.synced,
-            pr_head_sha=self.synced, pr_number=PR_NUMBER,
-            competing_live_locks=[], candidate_branches=[BRANCH],
-            current_pid=os.getpid(),
-            remote_branch_exists=True,
-            sync_provenance=sync_prov(self.prior, self.synced),
-        )
-        kw.update(over)
-        return issue_lock_recovery.assess_dead_session_lock_recovery(lock, **kw)
-
-    def test_merge_sync_drift_is_recoverable(self):
-        """AC3/AC4: dead session, recorded head is a merge-sync ancestor of PR head."""
-        res = self._assess()
-        self.assertEqual(res["outcome"], issue_lock_recovery.RECOVERY_SANCTIONED, res["reasons"])
-        self.assertEqual(
-            res["evidence"]["head_relation"],
-            issue_lock_recovery.HEAD_RELATION_REMOTE_MERGE_SYNCED,
-        )
-        self.assertEqual(res["evidence"]["accepted_head"], self.synced)
-
-    def test_missing_provenance_fails_closed(self):
-        """No server-derived provenance → cannot accept a remote ahead of local."""
-        res = self._assess(sync_provenance=None)
-        self.assertEqual(res["outcome"], issue_lock_recovery.REFUSED)
-
-    def test_non_ancestor_recorded_head_fails_closed(self):
-        """AC7: provenance that does not prove ancestry is rejected."""
-        res = self._assess(
-            sync_provenance=sync_prov(
-                self.prior, self.synced, prior_is_ancestor=False, is_merge_sync=False,
-                reasons=["prior head is not an ancestor"],
-            )
-        )
-        self.assertEqual(res["outcome"], issue_lock_recovery.REFUSED)
-
-    def test_force_pushed_history_fails_closed(self):
-        """AC8: a rewritten head (not a merge sync) stays protected."""
-        res = self._assess(
-            sync_provenance=sync_prov(
-                self.prior, self.synced, is_merge_sync=False, synced_is_merge=False,
-                reasons=["not a merge-based sync"],
-            )
-        )
-        self.assertEqual(res["outcome"], issue_lock_recovery.REFUSED)
-
-    def test_provenance_for_other_commits_fails_closed(self):
-        """Provenance whose endpoints differ from the heads under assessment is rejected."""
-        res = self._assess(
-            sync_provenance=sync_prov("f" * 40, self.synced),
-        )
-        self.assertEqual(res["outcome"], issue_lock_recovery.REFUSED)
-
-    def test_dirty_worktree_fails_closed(self):
-        """AC11: dirty worktrees remain protected."""
-        res = self._assess(porcelain_status=" M feature.txt\n")
-        self.assertEqual(res["outcome"], issue_lock_recovery.REFUSED)
-
-    def test_live_owner_fails_closed(self):
-        """AC10: a live recorded owner is not a dead-session recovery."""
-        lock = make_dead_lock(self.tmp, session_pid=os.getpid(), pid=os.getpid())
-        res = self._assess(_lock=lock)
-        self.assertEqual(res["outcome"], issue_lock_recovery.REFUSED)
-
-    def test_competing_claimant_fails_closed(self):
-        """AC13: a competing live lock blocks recovery."""
-        res = self._assess(
-            competing_live_locks=[{
-                "issue_number": ISSUE, "branch_name": BRANCH,
-                "worktree_path": "/some/other/wt", "pid": os.getpid(),
-            }]
-        )
-        self.assertEqual(res["outcome"], issue_lock_recovery.REFUSED)
-
-    def test_wrong_branch_fails_closed(self):
-        """AC9: worktree on a different branch fails closed."""
-        res = self._assess(current_branch="fix/issue-8710-other")
-        self.assertEqual(res["outcome"], issue_lock_recovery.REFUSED)
-
-    def test_wrong_identity_fails_closed(self):
-        res = self._assess(identity="intruder")
-        self.assertEqual(res["outcome"], issue_lock_recovery.REFUSED)
-
-    def test_pr_head_mismatch_fails_closed(self):
-        """The open PR must sit at the synced remote head."""
-        res = self._assess(pr_head_sha="e" * 40)
-        self.assertEqual(res["outcome"], issue_lock_recovery.REFUSED)
-
-    def test_owning_pr_evidence_for_merge_sync(self):
-        res = self._assess()
-        ev = issue_lock_recovery.owning_pr_recovery_evidence(res)
-        self.assertIsNotNone(ev)
-        self.assertEqual(ev["pr_number"], PR_NUMBER)
-        self.assertEqual(ev["head_sha"], self.synced)
-        self.assertEqual(
-            ev["head_relation"],
-            issue_lock_recovery.HEAD_RELATION_REMOTE_MERGE_SYNCED,
-        )
-
-    def test_recovered_owning_pr_from_persisted_record(self):
-        res = self._assess()
-        record = issue_lock_recovery.build_recovery_record(res, recovered_at=future_ts(0))
-        lock = {"issue_number": ISSUE, "branch_name": BRANCH,
-                "dead_session_recovery": record}
-        rebuilt = issue_lock_recovery.recovered_owning_pr_from_lock(lock)
-        self.assertIsNotNone(rebuilt)
-        self.assertEqual(rebuilt["head_sha"], self.synced)
-        self.assertEqual(
-            rebuilt["head_relation"],
-            issue_lock_recovery.HEAD_RELATION_REMOTE_MERGE_SYNCED,
-        )
-
-
-class TestExistingRelationsUnchanged(unittest.TestCase):
-    """AC14/AC15: equal-head recovery still works; merge-sync did not weaken it."""
-
-    def setUp(self):
-        self.tmp = tempfile.mkdtemp()
-        self.shas = build_merge_sync_repo(self.tmp)
-
-    def test_equal_head_recovery_still_sanctioned(self):
-        # Worktree at prior head; remote also at prior head → the #753 equal case.
-        prior = self.shas["prior"]
-        lock = make_dead_lock(self.tmp)
-        res = issue_lock_recovery.assess_dead_session_lock_recovery(
-            lock, issue_number=ISSUE, branch_name=BRANCH, worktree_path=self.tmp,
-            remote=REMOTE, org=ORG, repo=REPO, identity=IDENTITY, profile=PROFILE,
-            current_branch=BRANCH, porcelain_status="",
-            head_sha=prior, remote_head_sha=prior,
-            pr_head_sha=prior, pr_number=PR_NUMBER,
-            competing_live_locks=[], candidate_branches=[BRANCH],
-            current_pid=os.getpid(), remote_branch_exists=True,
-        )
-        self.assertEqual(res["outcome"], issue_lock_recovery.RECOVERY_SANCTIONED, res["reasons"])
-        self.assertEqual(
-            res["evidence"]["head_relation"], issue_lock_recovery.HEAD_RELATION_EQUAL,
-        )
-
-
-class TestUpdatePrWrapperPartialFailure(unittest.TestCase):
-    """AC5/AC16: the tool advances the remote head then refreshes the durable lock.
-
-    When the durable refresh fails after the remote advance, the tool must report a
-    partial lifecycle failure and NOT a fully successful synchronization. Exact PR-
-    head / base-head pinning is preserved (delegated to the real preflight, stubbed
-    here only to isolate the post-update lifecycle branch).
-    """
-
-    def setUp(self):
-        import gitea_mcp_server as gms  # noqa: E402
-        self.gms = gms
-        self._orig = {}
-
-        def _patch(name, value):
-            self._orig[name] = getattr(gms, name)
-            setattr(gms, name, value)
-
-        _patch("get_profile", lambda *a, **k: {
-            "allowed_operations": ["gitea.branch.push"],
-            "forbidden_operations": [],
-            "profile_name": "prgs-author",
-        })
-        _patch("_role_kind", lambda *a, **k: "author")
-        _patch("_profile_operation_gate", lambda *a, **k: None)
-        _patch("_permission_block_report", lambda *a, **k: {})
-        _patch("_resolve", lambda *a, **k: ("gitea.prgs.cc", ORG, REPO))
-        _patch("_verify_role_mutation_workspace", lambda *a, **k: None)
-        _patch("_get_workspace_porcelain", lambda *a, **k: "")
-        _patch("_canonical_local_git_root", lambda *a, **k: "/x")
-        _patch("_master_parity_block", lambda *a, **k: None)
-        _patch("_auth", lambda *a, **k: {"token": "x"})
-        _patch("repo_api_url", lambda *a, **k: "http://api")
-        _patch("_redact", lambda s: s)
-        _patch("_work_lease_claimant", lambda *a, **k: {
-            "username": IDENTITY, "profile": PROFILE,
-        })
-        _patch("_prove_author_ownership_for_pr", lambda *a, **k: {
-            "has_author_lock": True, "matched_issue": ISSUE,
-            "matched_via": "branch", "linked_issues": [ISSUE],
-            "recovered_owning_pr": None, "reasons": [],
-        })
-
-        # Real preflight is unit-tested elsewhere; stub it to isolate the
-        # post-update durable-lock lifecycle branch under test.
-        orig_pf = gms.pr_sync_status.assess_update_pr_branch_preflight
-        self._orig_pf = orig_pf
-        gms.pr_sync_status.assess_update_pr_branch_preflight = (
-            lambda *a, **k: {"mutation_allowed": True, "reasons": [], "performed": False}
-        )
-
-        # Sequence the two GET /pulls calls: OLD before update, NEW after.
-        self._pull_calls = {"n": 0}
-
-        def fake_api_request(method, url, auth, *a, **k):
-            m = method.upper()
-            if m == "GET" and url.endswith(f"/pulls/{PR_NUMBER}"):
-                self._pull_calls["n"] += 1
-                head = OLD if self._pull_calls["n"] == 1 else NEW1
-                return {
-                    "state": "open",
-                    "head": {"sha": head, "ref": BRANCH},
-                    "base": {"sha": BASE, "ref": "master"},
-                    "mergeable": True, "title": "t", "body": "b",
-                }
-            if m == "GET" and "/branches/" in url:
-                return {"commit": {"id": BASE}}
-            if m == "POST" and "/update" in url:
-                return {}
-            return {}
-
-        _patch("api_request", fake_api_request)
-
-    def tearDown(self):
-        for name, value in self._orig.items():
-            setattr(self.gms, name, value)
-        self.gms.pr_sync_status.assess_update_pr_branch_preflight = self._orig_pf
-
-    def _run(self):
-        return self.gms.gitea_update_pr_branch_by_merge(
-            pr_number=PR_NUMBER,
-            expected_pr_head_sha=OLD,
-            expected_base_head_sha=BASE,
-            remote=REMOTE,
-            worktree_path="/tmp/branches/wt-871",
-        )
-
-    def test_partial_failure_when_refresh_fails(self):
-        self._orig["apply_durable_lock_head_refresh"] = (
-            self.gms.issue_lock_store.apply_durable_lock_head_refresh
-        )
-        self.gms.issue_lock_store.apply_durable_lock_head_refresh = (
-            lambda **k: {"refreshed": False, "reasons": ["forced refresh failure"]}
-        )
-        try:
-            res = self._run()
-        finally:
-            self.gms.issue_lock_store.apply_durable_lock_head_refresh = (
-                self._orig["apply_durable_lock_head_refresh"]
-            )
-        self.assertTrue(res["performed"])
-        self.assertEqual(res["new_pr_head_sha"], NEW1)
-        self.assertFalse(res["success"])
-        self.assertTrue(res["partial_lifecycle_failure"])
-        self.assertFalse(res["durable_lock_refreshed"])
-
-    def test_full_success_when_refresh_succeeds(self):
-        self._orig["apply_durable_lock_head_refresh"] = (
-            self.gms.issue_lock_store.apply_durable_lock_head_refresh
-        )
-        self.gms.issue_lock_store.apply_durable_lock_head_refresh = (
-            lambda **k: {"refreshed": True, "read_after_write_ok": True,
-                         "new_head": NEW1, "reasons": ["ok"]}
-        )
-        try:
-            res = self._run()
-        finally:
-            self.gms.issue_lock_store.apply_durable_lock_head_refresh = (
-                self._orig["apply_durable_lock_head_refresh"]
-            )
-        self.assertTrue(res["success"])
-        self.assertTrue(res["performed"])
-        self.assertTrue(res["durable_lock_refreshed"])
-        self.assertTrue(res["fully_synchronized"])
-        self.assertEqual(res["new_pr_head_sha"], NEW1)
-
-
-if __name__ == "__main__":
-    unittest.main()
@@ -1,107 +0,0 @@
-"""Documentation acceptance for the MCP restart governance ADR (#656).
-
-Enforces issue #656 acceptance criteria:
-
-* AC1 — policy document exists with an authorization matrix and the recorded
-  v1 decision (controller approval + automated safety gates).
-* AC2 — restart is stated as a last resort with enumerated narrower recoveries.
-* AC3 — a unilateral LLM full restart with affected sessions is forbidden.
-* AC4 — break-glass conditions are listed.
-* AC5 — the ADR is linked to #655, #652, #653, #630, #642, and is cross-linked
-  from the safety model and the web-console deployment boundary docs.
-"""
-from pathlib import Path
-
-REPO_ROOT = Path(__file__).resolve().parent.parent
-ADR = REPO_ROOT / "docs" / "architecture" / "mcp-restart-governance.md"
-ADR_BASENAME = "mcp-restart-governance.md"
-
-CROSS_LINK_DOCS = (
-    REPO_ROOT / "docs" / "safety-model.md",
-    REPO_ROOT / "docs" / "webui-deployment.md",
-)
-
-LINKED_ISSUES = ("#655", "#652", "#653", "#630", "#642")
-POLICY_IDS = ("RG-01", "RG-02", "RG-03", "RG-04", "RG-05", "RG-06", "RG-07", "RG-08")
-
-
-def _read(path: Path) -> str:
-    assert path.is_file(), f"missing {path.relative_to(REPO_ROOT)}"
-    return path.read_text(encoding="utf-8")
-
-
-def test_ac1_adr_exists_with_matrix_and_v1_decision():
-    text = _read(ADR)
-    lower = text.lower()
-    assert text.lstrip().startswith("#"), "ADR lacks a title"
-    assert "#656" in text
-    assert "authorization matrix" in lower
-    # The matrix is a real table with the worker and privileged roles.
-    for role in ("author", "reviewer", "merger", "reconciler", "controller",
-                 "operator", "admin"):
-        assert role in lower, f"authorization matrix missing role {role!r}"
-    # Recorded v1 decision.
-    assert "restart-governance/v1" in text
-    assert "controller approval" in lower and "automated safety gates" in lower
-
-
-def test_ac2_restart_is_last_resort_with_narrower_recoveries():
-    text = _read(ADR)
-    lower = text.lower()
-    assert "last resort" in lower
-    # Enumerated narrower recoveries precede full restart on the ladder.
-    for rung in ("reconnect", "rebind", "scoped restart", "full restart",
-                 "host"):
-        assert rung in lower, f"recovery ladder missing rung {rung!r}"
-
-
-def test_ac3_forbids_unilateral_llm_full_restart_with_affected_sessions():
-    text = _read(ADR)
-    lower = text.lower()
-    assert "forbidden" in lower
-    assert "llm" in lower and "restart" in lower
-    assert "unilateral" in lower
-    # A worker role must not perform or authorize full/host restart.
-    assert "must not" in lower
-
-
-def test_ac4_break_glass_conditions_listed():
-    text = _read(ADR)
-    lower = text.lower()
-    assert "break-glass" in lower
-    assert "incident" in lower
-    assert "audit" in lower
-
-
-def test_ac5_adr_links_issue_lineage():
-    text = _read(ADR)
-    for issue in LINKED_ISSUES:
-        assert issue in text, f"ADR must link issue {issue}"
-
-
-def test_ac5_safety_model_and_deployment_cross_link_adr():
-    for path in CROSS_LINK_DOCS:
-        text = _read(path)
-        assert ADR_BASENAME in text, (
-            f"{path.relative_to(REPO_ROOT)} must cross-link {ADR_BASENAME} "
-            f"(issue #656 acceptance criterion 5)"
-        )
-
-
-def test_policy_ids_present_for_enforcement_code():
-    text = _read(ADR)
-    for pid in POLICY_IDS:
-        assert pid in text, f"policy id {pid} missing from ADR"
-
-
-def test_failure_behavior_denies_on_ambiguity():
-    text = _read(ADR)
-    lower = text.lower()
-    assert "ambiguous" in lower and "deny" in lower
-
-
-def test_cross_links_do_not_embed_secrets():
-    for path in (ADR,) + CROSS_LINK_DOCS:
-        text = _read(path)
-        for marker in ("ghp_", "BEGIN PRIVATE KEY", "Authorization: Bearer"):
-            assert marker not in text, f"{path} contains {marker!r}"
@@ -134,35 +134,13 @@ class TestClassification(unittest.TestCase):
        self.assertEqual(cls, wca.CLASS_ACTIVE_OPEN_PR)
        self.assertFalse(wca.is_removable(cls))

-    def test_stale_clean_issue_worktree_needs_merged_pr_proof(self):
-        # Scenario 5 (#858): age is not proof that the branch landed, so a
-        # TTL-expired issue worktree stays active work. Only authoritative
-        # merged-PR evidence makes it removable, which is what keeps a
-        # worktree holding unmerged commits from being reclaimed by age.
+    def test_stale_clean_issue_worktree_removable(self):
+        # Scenario 5: clean issue worktree, TTL expired, no lock -> removable.
        cls = wca.classify_worktree(
            workflow_type=wca.WORKFLOW_ISSUE_WORK,
            is_dirty=False,
            ttl_expired=True,
        )
-        self.assertEqual(cls, wca.CLASS_ACTIVE_ISSUE_WORK)
-        self.assertFalse(wca.is_removable(cls))
-
-        cls = wca.classify_worktree(
-            workflow_type=wca.WORKFLOW_ISSUE_WORK,
-            is_dirty=False,
-            ttl_expired=True,
-            merged_pr_cleanup={"proven": True},
-        )
-        self.assertEqual(cls, wca.CLASS_CLEAN_STALE_REMOVABLE)
-        self.assertTrue(wca.is_removable(cls))
-
-    def test_stale_clean_conflict_fix_worktree_removable(self):
-        # conflict_fix keeps the original TTL rule; #858 changed issue work only.
-        cls = wca.classify_worktree(
-            workflow_type=wca.WORKFLOW_CONFLICT_FIX,
-            is_dirty=False,
-            ttl_expired=True,
-        )
        self.assertEqual(cls, wca.CLASS_CLEAN_STALE_REMOVABLE)
        self.assertTrue(wca.is_removable(cls))

@@ -34,11 +34,7 @@ import subprocess
 from datetime import datetime, timezone
 from typing import Any

-from merged_cleanup_reconcile import (
-    branch_worktree_folder,
-    is_head_ancestor_of_ref,
-    read_local_worktree_state,
-)
+from merged_cleanup_reconcile import branch_worktree_folder, read_local_worktree_state
 from reviewer_worktree import parse_dirty_tracked_files, REVIEW_WORKTREE_RE

 PROTECTED_BRANCHES = frozenset({"master", "main", "dev"})
@@ -71,14 +67,6 @@ REMOVABLE_CLASSES = frozenset(
    {CLASS_CLEAN_STALE_REMOVABLE, CLASS_DETACHED_REVIEW_LEFTOVER}
 )

-# Merged-PR linkage outcomes for issue worktrees (#858). Only ``LINKAGE_MERGED``
-# is ownership proof; every other outcome leaves the worktree protected.
-LINKAGE_MERGED = "merged_pr"
-LINKAGE_OPEN = "open_pr"
-LINKAGE_NONE = "no_owning_pr"
-LINKAGE_AMBIGUOUS = "ambiguous"
-LINKAGE_UNKNOWN = "unknown"
-
 _ISSUE_REF_RE = re.compile(r"issue-(\d+)", re.IGNORECASE)
 _ISSUE_BRANCH_PREFIXES = ("feat/", "fix/", "docs/", "chore/")

@@ -181,186 +169,6 @@ def is_ttl_expired(
    return (now_dt - last).total_seconds() > ttl_hours * 3600.0


-def build_pr_index(prs: list[dict[str, Any]] | None) -> dict[str, list[dict[str, Any]]]:
-    """Index PR records by head branch for deterministic worktree linkage (#858).
-
-    Accepts Gitea PR payloads (``head`` as a dict) and pre-flattened records
-    (``head_branch``/``head_sha``). Records without a usable head branch or
-    number are dropped rather than guessed at, so a branch is only ever linked
-    to a PR the caller actually proved.
-    """
-    index: dict[str, list[dict[str, Any]]] = {}
-    for pr in prs or []:
-        head = pr.get("head")
-        if isinstance(head, dict):
-            head_branch = head.get("ref")
-            head_sha = head.get("sha")
-        else:
-            head_branch = pr.get("head_branch") or (head if isinstance(head, str) else None)
-            head_sha = pr.get("head_sha")
-        number = pr.get("number")
-        if not head_branch or number is None:
-            continue
-        try:
-            pr_number = int(number)
-        except (TypeError, ValueError):
-            continue
-        index.setdefault(str(head_branch).strip(), []).append(
-            {
-                "pr_number": pr_number,
-                "head_branch": str(head_branch).strip(),
-                "head_sha": head_sha,
-                "merged": bool(pr.get("merged") or pr.get("merged_at")),
-                "state": pr.get("state"),
-            }
-        )
-    return index
-
-
-def resolve_owning_pr(
-    *,
-    branch: str | None,
-    pr_index: dict[str, list[dict[str, Any]]] | None,
-) -> dict[str, Any]:
-    """Resolve the single PR that owns ``branch``, failing closed when unclear.
-
-    Ownership is only ``LINKAGE_MERGED`` when exactly one PR claims the branch
-    and that PR is merged. Several distinct PRs on one branch is a competing
-    claim (``LINKAGE_AMBIGUOUS``), and a still-open owner is reported as
-    ``LINKAGE_OPEN`` — both keep the worktree protected while still exposing
-    the PR number the audit resolved.
-    """
-    if pr_index is None:
-        return {
-            "status": LINKAGE_UNKNOWN,
-            "pr_number": None,
-            "candidate_pr_numbers": [],
-            "reasons": ["live PR state was not supplied; ownership unproven"],
-        }
-    branch_name = (branch or "").strip()
-    if not branch_name:
-        return {
-            "status": LINKAGE_UNKNOWN,
-            "pr_number": None,
-            "candidate_pr_numbers": [],
-            "reasons": ["worktree has no attached branch; ownership unproven"],
-        }
-
-    candidates = list(pr_index.get(branch_name) or [])
-    numbers = sorted({c["pr_number"] for c in candidates})
-    if not candidates:
-        return {
-            "status": LINKAGE_NONE,
-            "pr_number": None,
-            "candidate_pr_numbers": [],
-            "reasons": [f"no PR claims branch '{branch_name}'"],
-        }
-    if len(numbers) > 1:
-        return {
-            "status": LINKAGE_AMBIGUOUS,
-            "pr_number": None,
-            "candidate_pr_numbers": numbers,
-            "reasons": [
-                f"branch '{branch_name}' is claimed by competing PRs {numbers}; "
-                "ownership is ambiguous"
-            ],
-        }
-
-    owner = candidates[0]
-    pr_number = owner["pr_number"]
-    if owner.get("head_branch") != branch_name:
-        return {
-            "status": LINKAGE_UNKNOWN,
-            "pr_number": pr_number,
-            "candidate_pr_numbers": numbers,
-            "reasons": [
-                f"PR #{pr_number} head branch '{owner.get('head_branch')}' does not "
-                f"match worktree branch '{branch_name}'"
-            ],
-        }
-    if not owner.get("merged"):
-        return {
-            "status": LINKAGE_OPEN,
-            "pr_number": pr_number,
-            "candidate_pr_numbers": numbers,
-            "pr_head_sha": owner.get("head_sha"),
-            "reasons": [f"owning PR #{pr_number} is not merged"],
-        }
-    return {
-        "status": LINKAGE_MERGED,
-        "pr_number": pr_number,
-        "candidate_pr_numbers": numbers,
-        "pr_head_sha": owner.get("head_sha"),
-        "reasons": [],
-    }
-
-
-def assess_merged_pr_worktree_cleanup(
-    *,
-    linkage: dict[str, Any] | None,
-    head_sha: str | None,
-    head_in_master: bool | None,
-    is_dirty: bool,
-    has_open_pr: bool,
-    has_active_lease: bool,
-    has_active_issue_lock: bool,
-    is_protected: bool,
-    has_live_session: bool = False,
-) -> dict[str, Any]:
-    """Decide whether a merged issue worktree satisfies the full cleanup policy.
-
-    Every condition must be independently proven: conclusive merged-PR
-    ownership, agreement between the worktree branch and the PR head branch,
-    containment of the worktree head in authoritative master (which is what
-    proves no unmerged commits remain), absence of any open/competing PR,
-    lease, issue lock, or live session, a clean tree, and a worktree that is
-    not the protected control checkout. Anything unknown blocks.
-    """
-    link = linkage or {
-        "status": LINKAGE_UNKNOWN,
-        "pr_number": None,
-        "reasons": ["no linkage assessment supplied"],
-    }
-    status = link.get("status")
-    reasons: list[str] = []
-
-    if status != LINKAGE_MERGED:
-        reasons.extend(
-            link.get("reasons") or ["owning PR could not be conclusively identified"]
-        )
-    if is_protected:
-        reasons.append("worktree is protected or the stable control checkout")
-    if is_dirty:
-        reasons.append("worktree has uncommitted changes")
-    if has_open_pr:
-        reasons.append("worktree branch has an open PR")
-    if has_active_lease:
-        reasons.append("worktree has an active lease")
-    if has_active_issue_lock:
-        reasons.append("an active issue lock references this branch")
-    if has_live_session:
-        reasons.append("a live process or session is using this worktree")
-    if not head_sha:
-        reasons.append("worktree head sha is unknown")
-    if head_in_master is None:
-        reasons.append("containment of the worktree head in master is unknown")
-    elif not head_in_master:
-        reasons.append(
-            "worktree head is not contained in authoritative master "
-            "(unmerged commits remain)"
-        )
-
-    proven = not reasons
-    return {
-        "linkage_status": status,
-        "pr_number": link.get("pr_number"),
-        "pr_head_sha": link.get("pr_head_sha"),
-        "head_in_master": head_in_master,
-        "proven": proven,
-        "block_reasons": reasons,
-    }
-
-
 def classify_worktree(
    *,
    workflow_type: str,
@@ -373,8 +181,6 @@ def classify_worktree(
    ttl_expired: bool = False,
    is_protected: bool = False,
    metadata_known: bool = True,
-    merged_pr_cleanup: dict[str, Any] | None = None,
-    has_live_session: bool = False,
 ) -> str:
    """Classify a worktree, safety-first: any preservation signal wins.

@@ -393,8 +199,6 @@ def classify_worktree(
        return CLASS_ACTIVE_ISSUE_WORK  # never auto-deleted (criterion 8)
    if has_active_issue_lock:
        return CLASS_ACTIVE_ISSUE_WORK
-    if has_live_session:
-        return CLASS_ACTIVE_ISSUE_WORK  # a live session still owns this tree
    if not metadata_known or workflow_type == WORKFLOW_UNKNOWN:
        return CLASS_UNSAFE_UNKNOWN  # never auto-deleted without proof

@@ -403,15 +207,7 @@ def classify_worktree(
        if is_detached or branch_gone:
            return CLASS_DETACHED_REVIEW_LEFTOVER
        return CLASS_CLEAN_STALE_REMOVABLE
-    if workflow_type == WORKFLOW_ISSUE_WORK:
-        # #858: an issue worktree becomes removable only on authoritative
-        # merged-PR evidence satisfying the whole cleanup policy. Age alone
-        # never proves the branch landed, so TTL cannot qualify one by itself
-        # — otherwise a worktree holding unmerged commits would be reclaimed.
-        if (merged_pr_cleanup or {}).get("proven"):
-            return CLASS_CLEAN_STALE_REMOVABLE
-        return CLASS_ACTIVE_ISSUE_WORK
-    # conflict_fix: only removable once the TTL has expired.
+    # issue_work / conflict_fix: only removable once the TTL has expired.
    if ttl_expired:
        return CLASS_CLEAN_STALE_REMOVABLE
    return CLASS_ACTIVE_ISSUE_WORK
@@ -604,20 +400,6 @@ def remove_worktree(project_root: str, path: str) -> dict[str, Any]:
    }


-def head_contained_in_ref(
-    project_root: str, head_sha: str | None, ref: str | None
-) -> bool | None:
-    """Return True when ``head_sha`` is already contained in ``ref``.
-
-    Shares :mod:`merged_cleanup_reconcile`'s ancestry check so the audit and
-    the PR-scoped reconciler agree on what "already landed" means (#858).
-    Returns None when containment cannot be determined, which fails closed.
-    """
-    if not head_sha or not ref:
-        return None
-    return is_head_ancestor_of_ref(project_root, head_sha, ref)
-
-
 def _is_under_branches(project_root: str, path: str) -> bool:
    branches_root = os.path.join(os.path.abspath(project_root), "branches")
    return os.path.abspath(path or "").startswith(branches_root + os.sep)
@@ -631,30 +413,16 @@ def audit_branches_directory(
    active_issue_branches: set[str] | None = None,
    now: datetime | str | None = None,
    ttl_hours: float = DEFAULT_TTL_HOURS,
-    pr_index: dict[str, list[dict[str, Any]]] | None = None,
-    leased_issue_numbers: set[int] | None = None,
-    live_session_paths: set[str] | None = None,
-    master_ref: str | None = None,
 ) -> dict[str, Any]:
    """Classify every session-owned worktree under ``branches/``.

    Read-only: shells out to git for discovery and dirty state, then applies
    the pure classifier. Returns per-worktree classifications, counts, the
    list of removable candidates, and the ``git worktree list`` proof.
-
-    ``pr_index`` (see :func:`build_pr_index`) supplies the authoritative PR
-    ownership used to link issue worktrees to their merged PR (#858).
-    ``master_ref`` is the ref a worktree head must be contained in before it
-    can be considered landed. Both are optional and their absence only ever
-    fails closed: without them no issue worktree becomes removable.
    """
    open_pr_branches = open_pr_branches or set()
    leased_branches = leased_branches or set()
    active_issue_branches = active_issue_branches or set()
-    leased_issue_numbers = leased_issue_numbers or set()
-    live_session_paths = {
-        os.path.abspath(p) for p in (live_session_paths or set()) if p
-    }

    worktrees: list[dict[str, Any]] = []
    for entry in list_worktrees(project_root):
@@ -665,42 +433,12 @@ def audit_branches_directory(
        )
        dirty_state = read_worktree_dirty(path)
        is_dirty = bool(dirty_state.get("dirty"))
-        head_sha = entry.get("head")
-        linkage = resolve_owning_pr(branch=branch, pr_index=pr_index)
        metadata = build_worktree_metadata(
-            path=path,
-            branch=branch,
-            head_sha=head_sha,
-            pr_number=linkage.get("pr_number"),
+            path=path, branch=branch, head_sha=entry.get("head")
        )
        has_open_pr = bool(branch) and branch in open_pr_branches
-        # A lease on issue N protects that issue's own work worktree. It must
-        # not incidentally protect a baseline/review scratch tree that merely
-        # carries the same issue marker in its name, which would change the
-        # classification of worktrees this policy does not own.
-        has_active_lease = (bool(branch) and branch in leased_branches) or (
-            metadata["workflow_type"] == WORKFLOW_ISSUE_WORK
-            and metadata.get("issue_number") is not None
-            and metadata["issue_number"] in leased_issue_numbers
-        )
+        has_active_lease = bool(branch) and branch in leased_branches
        has_active_lock = bool(branch) and branch in active_issue_branches
-        has_live_session = bool(path) and os.path.abspath(path) in live_session_paths
-        head_in_master = (
-            head_contained_in_ref(project_root, head_sha, master_ref)
-            if master_ref
-            else None
-        )
-        merged_pr_cleanup = assess_merged_pr_worktree_cleanup(
-            linkage=linkage,
-            head_sha=head_sha,
-            head_in_master=head_in_master,
-            is_dirty=is_dirty,
-            has_open_pr=has_open_pr,
-            has_active_lease=has_active_lease,
-            has_active_issue_lock=has_active_lock,
-            is_protected=is_protected,
-            has_live_session=has_live_session,
-        )
        ttl_expired = is_ttl_expired(
            last_used_at=metadata.get("last_used_at"), now=now, ttl_hours=ttl_hours
        )
@@ -714,8 +452,6 @@ def audit_branches_directory(
            branch_gone=branch is None and not entry.get("detached"),
            ttl_expired=ttl_expired,
            is_protected=is_protected,
-            merged_pr_cleanup=merged_pr_cleanup,
-            has_live_session=has_live_session,
        )
        metadata["cleanup_eligibility"] = classification
        worktrees.append(
@@ -727,10 +463,7 @@ def audit_branches_directory(
                "has_open_pr": has_open_pr,
                "has_active_lease": has_active_lease,
                "has_active_issue_lock": has_active_lock,
-                "has_live_session": has_live_session,
                "is_protected": is_protected,
-                "merged_pr_linkage": linkage,
-                "merged_pr_cleanup": merged_pr_cleanup,
                "classification": classification,
                "removable": is_removable(classification),
            }
Author	SHA1	Message	Date
jcwalker3	6a636c58e7	Merge branch 'master' into fix/issue-790-slice-a-heartbeat-policy	2026-07-23 19:52:27 -05:00
jcwalker3	d2fe0110a0	Merge branch 'master' into fix/issue-790-slice-a-heartbeat-policy	2026-07-23 19:13:01 -05:00
jcwalker3	f1e4809930	Merge branch 'master' into fix/issue-790-slice-a-heartbeat-policy	2026-07-23 12:31:44 -05:00
jcwalker3	dc1d0e045f	Merge branch 'master' into fix/issue-790-slice-a-heartbeat-policy	2026-07-23 01:13:11 -05:00
jcwalker3	badc4e636b	Merge branch 'master' into fix/issue-790-slice-a-heartbeat-policy	2026-07-23 00:06:18 -05:00
sysadminandClaude Opus 4.8	243f52dc79	feat(lease): make the author task heartbeat load-bearing (#790 Slice A) Slice A of Issue #790, per the controller reassessment in comment 13958. Does not close the issue: terminal retirement (Slice B) and the read-side generation check plus the #760 renewal re-scope (Slice C) are deliberately not implemented. The defect. `issue_lock_store.assess_lock_freshness` parsed `last_heartbeat_at` and then never consulted it. Liveness was decided by an absolute four-hour `expires_at` and by PID liveness, and the recorded PID is the long-lived MCP daemon rather than the authoring task, so an abandoned claim stayed live for the full four hours. A tree-wide search found the field written in exactly one place and advanced by nothing. Issue #787 / PR #789 hit this; Issue #760 / PR #791 hit it again, blocking reconciliation for over five hours after its work had landed. A1 — central policy. New `lease_policy` declares every duration for every task class in one place: author initial/sliding TTL 10 minutes, heartbeat cadence 2, stale warning 5, missed-heartbeat grace 10, absolute cap 8 hours, recovery grace 10, terminal race-drain 2. It ships first so the first heartbeat and TTL behavior to run reads from it (AC-N7). The duplicated four-hour literal is gone from both `issue_lock_store` and `gitea_mcp_server`. Reviewer, merger, and conflict-fix classes are declared but not rewired — Slice C moves those call sites — and a test asserts the declaration still equals the constants #747 and `pr_work_lease` own, so the two cannot drift apart unnoticed. A2 — load-bearing freshness, with two deliberate asymmetries. An alive PID never establishes freshness anywhere (AC-N2); it is recorded as evidence and no branch returns live because of it. A dead PID still marks a lease stale, and that band still precedes every heartbeat evaluation, so #753 dead-session recovery keys on exactly the classification it always did. New bands `stale_missed_heartbeat` and `stale_absolute_cap` are classified in `branch_cleanup_guard` rather than falling through to unknown-status, and still block unless the ownership record proves `reclaim_allowed is True`. A heartbeat lease carrying no heartbeat is contradictory and fails closed. `assess_expired_lock_reclaim` accepts a lapsed heartbeat as reclaim grounds for heartbeat-lifecycle leases only: under this lifecycle the heartbeat is the liveness proof, and also requiring a dead PID would reinstate the original defect. A3/A4 — task-session identity and the writer. `mint_task_session_id` produces an ownership key containing no process identifier, since the daemon PID is reused by every task it serves and identifies none of them. `heartbeat_session_lock` writes inside the existing per-issue flock under the #772 generation compare-and-swap, verifying exact issue, branch, realpath-normalized worktree, claimant username, claimant profile, and recorded session identifier. It cannot acquire, take over, or revive: a lease past its grace is refused and must use the reclaim path, so a session that stopped proving liveness cannot restore ownership retroactively. New `gitea_heartbeat_issue_lock` gates on the same authority as `lock_issue`, being strictly narrower. A5 — legacy compatibility (AC-N8). The explicit `lifecycle_version` marker, never a timestamp comparison, discriminates legacy from heartbeat leases: a legacy lock has `last_heartbeat_at == created_at` forever precisely because nothing advanced it, and a freshly minted heartbeat lease has them equal too, so the equality carries no information in either direction. Legacy locks keep their recorded absolute expiry and are never evaluated against the short grace, so deployment cannot make an existing claim instantly reclaimable. They leave that state only by terminal retirement (Slice B) or by `rebind_legacy_lock`, which re-verifies the exact owner and mints a genuine identifier and first heartbeat while preserving the original claim under `legacy_origin`. Rebinding a lapsed legacy lease is refused; that belongs to #760 renewal or #601 reclaim. A6 — native coverage. Review #499 proved assessor-level tests miss discard points, so `tests/test_issue_790_heartbeat_mcp_path.py` drives the real tools against a real git repository and a real durable lock: lock creation and read-back, policy window, freshness, survival of `verify_lock_for_mutation`, invariance of the duplicate-work and linked-open-PR gates, CAS rejection, foreign-session and foreign-claimant refusal, alive-PID-only refusal, missed heartbeat, legacy protection on deployment, and legacy rebinding. Tests. New suites 55 passed. Lock and lease regression set (issue_lock_store, lease_lifecycle, #753, #755, #760 x2, #768, #772, lock registration, worktree, adoption, duplicate gate, branch cleanup guard, capability invariants, claim heartbeat, worktrees) 383 passed with 98 subtests. Full suite 4295 passed, 11 failed, 6 skipped, 499 subtests passed, against a clean master baseline worktree at `620ed6e9` that reports 11 failed and 4240 passed — the same eleven node IDs. The 55-test delta is exactly the new suites; no new failures. Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]> Claude-Session: https://claude.ai/code/session_011u6GKSJwwrrYjguPjs1aK5	2026-07-22 04:19:48 -04:00