fix(webui): repair traffic live path contracts for #640 review

Address PR #885 REQUEST_CHANGES: full head_sha pins from queue signals, reviewer leases keyed by pr_number only, claim inventory via entries, live-path fixture tests, and traffic state vocabulary docs. Closes #640 (re-review at new head) Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>
feat(webui): implement workflow traffic-control view (Closes #640 )
2026-07-24 18:31:28 -04:00 · 2026-07-24 17:34:50 -04:00
11 changed files with 1118 additions and 1171 deletions
@@ -57,6 +57,33 @@ status, onboarding checklist state, and the fail-closed error payloads (#635).
 | `/system-health` | System-health dashboard — readiness, version/uptime, dependencies, MCP namespaces, stale-runtime parity (#639) |
 | `/queue` | Live PR and issue queue dashboard (#429) |
 | `/api/queue` | JSON queue export with pagination metadata |
+| `/traffic` | Workflow traffic-control view — runnable, leased, blocked, needs-controller, terminal-complete (#640) |
+| `/api/traffic` | JSON traffic-control export with state classifications and next safe role actions |
+
+### Traffic-control state vocabulary (#640)
+
+The traffic view classifies each open issue/PR into exactly one bucket:
+
+| Bucket | Meaning | Operator implication |
+|--------|---------|----------------------|
+| **runnable** | No active lease, no block reason, safe for its expected role | Next role may start work |
+| **leased** | Active author claim or reviewer PR lease | Do not stomp; wait or adopt via role tools |
+| **blocked** | Dependency, missing head pin, conflict, or status:blocked | Author/controller remediation first |
+| **needs_controller** | Contaminated / controller-only diagnosis | Controller only |
+| **terminal_complete** | Reconciler / terminal-lock territory | Reconciler cleanup path |
+
+**Live path contracts (do not invent):**
+
+- PR head pins come from `QueueItem.signals["head_sha"]` (full SHA). Display
+  `extra["head_sha"]` is truncated and must never be used for routing.
+- Reviewer leases are keyed as `(pr, pr_number)` only — never via a linked
+  `issue_number` on the same lease marker.
+- Issue claims come from `claim_inventory["entries"]`
+  (`issue_claim_heartbeat.build_claim_inventory`). There is no `active_claims`
+  key.
+- Queue display badges are only: `blocked`, `claimed`, `duplicate`, `stale`,
+  `in-review`, `open`. Review verdicts (`request-changes`, `approved`) are
+  **not** queue badges; traffic does not invent them from the queue loader.
 | `/projects` | Project registry list with status and onboarding progress (#427, #635) |
 | `/projects/{id}` | Project detail + onboarding checklist |
 | `/api/v1/projects` | Versioned JSON registry export (#635) |
@@ -1,726 +0,0 @@
-"""Pre-restart drain proof and hard gate (#661).
-
-A sanctioned MCP restart may only proceed after a machine-verifiable *drain
-proof* attests that unsafe work is clear and checkpoints are complete. Drain
-mode alone (#659) is not enough: without a proof, an apply path could still
-restart on a stale or false "ready" claim, dropping mutations and orphaning
-leases. This module defines the :class:`DrainProof` artifact, a fail-closed
-verifier, and the hard gate the sanctioned restart-apply path must consult.
-
-Design rules (mirror :mod:`restart_coordinator` / :mod:`lease_lifecycle`):
-
-* **Pure classification.** Every function here operates on already-gathered
-  inputs and returns a structured result. Nothing touches the network, the
-  filesystem, or a live process, so multi-session fixtures drive every branch.
-  This module never restarts anything; the gate only *authorizes or denies*.
-* **Fail closed.** A missing, expired, tampered, or unclean proof denies the
-  restart. Unknown checkpoint completeness is treated as *not complete*. An
-  incomplete impact report can never yield a clean proof.
-* **Non-forgeable within the process.** The proof id is a keyed hash over the
-  canonical proof contents using a per-process secret. A worker session cannot
-  hand-craft a passing proof without that secret, and a proof minted in a prior
-  daemon process will not verify after a restart (the secret is regenerated).
-* **No secrets leak.** The per-process secret never appears in a proof, an
-  ``as_dict``, an audit record, or an incident descriptor.
-
-Relationship to siblings (#655 umbrella):
-
-* **#658** ``restart_coordinator.evaluate_restart_impact`` — produces the
-  blast-radius impact report this proof consumes ("what would a restart
-  disrupt?"). ``mutations`` / ``critical_sections`` being empty is what the
-  no-in-flight-mutations check verifies.
-* **#659** graceful drain mode — performs the drain actions and calls
-  :func:`build_drain_proof` to mint the artifact once its checklist passes.
-* **#660** durable session checkpoints — supplies checkpoint completeness.
-  Because that schema may not yet be present, completeness is an *input* here,
-  never a hard table dependency; unknown fails closed.
-
-Non-goals (separate children): the emergency break-glass *workflow* (this gate
-only leaves a sanctioned bypass hole authorized elsewhere), the console UI, and
-the actual restart execution.
-"""
-
-from __future__ import annotations
-
-import hashlib
-import hmac
-import json
-import os
-from dataclasses import dataclass
-from datetime import datetime, timedelta, timezone
-from typing import Any, Mapping, Sequence
-
-DRAIN_PROOF_VERSION = "1.0.0-issue-661"
-
-# Short default lifetime for a drain proof. A proof attests to a *point-in-time*
-# drained state; live work can resume the moment drain mode relaxes, so the
-# window in which a proof is honoured must be small (#661 security: short TTL).
-DEFAULT_PROOF_TTL_SECONDS = 120
-
-# Gate verdicts.
-GATE_ALLOW = "allow"
-GATE_DENY = "deny"
-GATE_BREAK_GLASS = "break_glass"
-
-# The mandatory drain checklist. A proof is *clean* only when every one of these
-# checks passed. Names are stable identifiers surfaced in audit + incidents.
-CHECK_NO_INFLIGHT_MUTATIONS = "no_inflight_mutations"
-CHECK_ASSIGNMENTS_STOPPED = "assignments_stopped"
-CHECK_CHECKPOINTS_COMPLETE = "checkpoints_complete"
-CHECK_HANDOFFS_OK = "handoffs_ok"
-CHECK_LEASES_HANDLED = "leases_handled"
-CHECK_ACKS_OR_TIMEOUT = "acks_or_timeout"
-
-REQUIRED_CHECKS: tuple[str, ...] = (
-    CHECK_NO_INFLIGHT_MUTATIONS,
-    CHECK_ASSIGNMENTS_STOPPED,
-    CHECK_CHECKPOINTS_COMPLETE,
-    CHECK_HANDOFFS_OK,
-    CHECK_LEASES_HANDLED,
-    CHECK_ACKS_OR_TIMEOUT,
-)
-
-
-def _utc_now() -> datetime:
-    return datetime.now(timezone.utc)
-
-
-def _parse_ts(value: str | None) -> datetime | None:
-    if not value:
-        return None
-    text = str(value).strip()
-    if not text:
-        return None
-    if text.endswith("Z"):
-        text = text[:-1] + "+00:00"
-    try:
-        dt = datetime.fromisoformat(text)
-    except ValueError:
-        return None
-    if dt.tzinfo is None:
-        dt = dt.replace(tzinfo=timezone.utc)
-    return dt
-
-
-def _canonical(payload: Any) -> str:
-    """Deterministic JSON encoding for hashing (stable key order, no spaces)."""
-
-    return json.dumps(payload, sort_keys=True, separators=(",", ":"), default=str)
-
-
-# ---------------------------------------------------------------------------
-# Per-process secret. Generated once per daemon process; regenerated on restart.
-# Injectable for tests so build + verify share a secret. Never serialized.
-# ---------------------------------------------------------------------------
-_PROCESS_SECRET = os.urandom(32)
-
-
-def process_secret() -> bytes:
-    """Return the per-process proof-signing secret (never serialized)."""
-
-    return _PROCESS_SECRET
-
-
-def _resolve_secret(secret: bytes | None) -> bytes:
-    return secret if secret is not None else _PROCESS_SECRET
-
-
-@dataclass(frozen=True)
-class DrainCheck:
-    """One mandatory drain checklist result."""
-
-    name: str
-    passed: bool
-    detail: str
-
-    def as_dict(self) -> dict[str, Any]:
-        return {"name": self.name, "passed": self.passed, "detail": self.detail}
-
-
-@dataclass(frozen=True)
-class DrainProof:
-    """Machine-verifiable proof that a restart's blast radius has been drained.
-
-    The ``proof_id`` is a keyed hash over the canonical proof body; it is the
-    tamper-evident signature verified at the gate. ``clean`` is True only when
-    every required check passed. The proof is honoured only until ``expires_at``.
-    """
-
-    version: str
-    proof_id: str
-    clean: bool
-    issued_at: str
-    expires_at: str
-    requesting_session_id: str | None
-    impact_fingerprint: str
-    checks: list[DrainCheck]
-    failed_checks: list[str]
-
-    def as_dict(self) -> dict[str, Any]:
-        return {
-            "version": self.version,
-            "proof_id": self.proof_id,
-            "clean": self.clean,
-            "issued_at": self.issued_at,
-            "expires_at": self.expires_at,
-            "requesting_session_id": self.requesting_session_id,
-            "impact_fingerprint": self.impact_fingerprint,
-            "checks": [c.as_dict() for c in self.checks],
-            "failed_checks": list(self.failed_checks),
-        }
-
-
-@dataclass(frozen=True)
-class VerifyResult:
-    """Outcome of :func:`verify_drain_proof` (fail closed)."""
-
-    valid: bool
-    reasons: list[str]
-    proof_id: str | None
-    clean: bool
-    expired: bool
-    tampered: bool
-
-    def as_dict(self) -> dict[str, Any]:
-        return {
-            "valid": self.valid,
-            "reasons": list(self.reasons),
-            "proof_id": self.proof_id,
-            "clean": self.clean,
-            "expired": self.expired,
-            "tampered": self.tampered,
-        }
-
-
-@dataclass(frozen=True)
-class GateDecision:
-    """Outcome of :func:`gate_apply_restart`."""
-
-    allow: bool
-    verdict: str
-    reasons: list[str]
-    proof_id: str | None
-    break_glass: bool
-    incident: dict[str, Any] | None
-    audit_record: dict[str, Any]
-
-    def as_dict(self) -> dict[str, Any]:
-        return {
-            "allow": self.allow,
-            "verdict": self.verdict,
-            "reasons": list(self.reasons),
-            "proof_id": self.proof_id,
-            "break_glass": self.break_glass,
-            "incident": self.incident,
-            "audit_record": dict(self.audit_record),
-        }
-
-
-def impact_fingerprint(impact_report: Mapping[str, Any] | None) -> str:
-    """Stable fingerprint of the blast-radius state a proof was minted against.
-
-    Binds a proof to the specific impact evaluation. If the live state changes
-    (a new mutation appears) between minting and gate, the caller can pass the
-    fresh fingerprint and the proof will be rejected as stale.
-    """
-
-    report = impact_report or {}
-    counts = report.get("counts") or {}
-    material = {
-        "inventory_complete": bool(report.get("inventory_complete", False)),
-        "verdict": report.get("verdict"),
-        "affected_issues": sorted(report.get("affected_issues") or []),
-        "affected_prs": sorted(report.get("affected_prs") or []),
-        "mutations": sorted(
-            str(m.get("lease_id"))
-            for m in (report.get("mutations") or [])
-            if isinstance(m, Mapping)
-        ),
-        "critical_sections": sorted(
-            str(c.get("lease_id"))
-            for c in (report.get("critical_sections") or [])
-            if isinstance(c, Mapping)
-        ),
-        "terminal_lock": bool(report.get("terminal_lock")),
-        "counts": {
-            k: counts.get(k)
-            for k in (
-                "sessions_live_other",
-                "leases_disruptive",
-                "critical_sections",
-                "mutations",
-            )
-        },
-    }
-    return hashlib.sha256(_canonical(material).encode("utf-8")).hexdigest()
-
-
-def _sign(body: Mapping[str, Any], secret: bytes) -> str:
-    """Keyed (HMAC-SHA256) signature over the canonical proof body."""
-
-    return hmac.new(
-        secret, _canonical(body).encode("utf-8"), hashlib.sha256
-    ).hexdigest()
-
-
-def _proof_body(
-    *,
-    clean: bool,
-    issued_at: str,
-    expires_at: str,
-    requesting_session_id: str | None,
-    fingerprint: str,
-    checks: Sequence[DrainCheck],
-) -> dict[str, Any]:
-    """The exact fields covered by the signature. Order-independent (canonical)."""
-
-    return {
-        "version": DRAIN_PROOF_VERSION,
-        "clean": clean,
-        "issued_at": issued_at,
-        "expires_at": expires_at,
-        "requesting_session_id": requesting_session_id,
-        "impact_fingerprint": fingerprint,
-        "checks": [c.as_dict() for c in checks],
-    }
-
-
-def _bool_input(value: Any) -> bool:
-    """Strictly interpret a drain-state flag; anything not explicitly True fails."""
-
-    return value is True
-
-
-def _evaluate_checks(
-    impact_report: Mapping[str, Any],
-    drain_state: Mapping[str, Any],
-) -> list[DrainCheck]:
-    """Compute the mandatory checklist from the impact report + drain outcomes.
-
-    The report answers "is unsafe work still in flight?"; ``drain_state`` reports
-    the drain-mode actions the coordinator/#659 performed. Every check fails
-    closed when its evidence is missing or ambiguous.
-    """
-
-    checks: list[DrainCheck] = []
-
-    inventory_complete = bool(impact_report.get("inventory_complete", False))
-    mutations = list(impact_report.get("mutations") or [])
-    critical = list(impact_report.get("critical_sections") or [])
-    disruptive = [
-        l
-        for l in (impact_report.get("affected_leases") or [])
-        if isinstance(l, Mapping) and l.get("disruptive")
-    ]
-
-    # 1. No in-flight mutations. Derived from the authoritative impact report,
-    #    not self-reported: a proof cannot claim "no mutations" while the report
-    #    still shows mutations or unsevered critical sections.
-    if not inventory_complete:
-        checks.append(
-            DrainCheck(
-                CHECK_NO_INFLIGHT_MUTATIONS,
-                False,
-                "impact report inventory incomplete; cannot confirm mutations "
-                "cleared (fail closed)",
-            )
-        )
-    elif mutations or critical:
-        checks.append(
-            DrainCheck(
-                CHECK_NO_INFLIGHT_MUTATIONS,
-                False,
-                f"{len(mutations)} mutation(s) and {len(critical)} critical "
-                "section(s) still in flight",
-            )
-        )
-    else:
-        checks.append(
-            DrainCheck(
-                CHECK_NO_INFLIGHT_MUTATIONS,
-                True,
-                "no in-flight mutations or critical sections in impact report",
-            )
-        )
-
-    # 2. New assignment halted (maintenance-drain entered).
-    checks.append(
-        DrainCheck(
-            CHECK_ASSIGNMENTS_STOPPED,
-            _bool_input(drain_state.get("assignments_stopped")),
-            "new work assignment halted"
-            if _bool_input(drain_state.get("assignments_stopped"))
-            else "assignments not confirmed stopped (fail closed)",
-        )
-    )
-
-    # 3. Durable checkpoints complete (#660). Unknown => not complete.
-    cp = drain_state.get("checkpoints_complete")
-    checks.append(
-        DrainCheck(
-            CHECK_CHECKPOINTS_COMPLETE,
-            _bool_input(cp),
-            "all live sessions checkpointed"
-            if _bool_input(cp)
-            else "checkpoint completeness unconfirmed (fail closed)",
-        )
-    )
-
-    # 4. Handoffs verified.
-    checks.append(
-        DrainCheck(
-            CHECK_HANDOFFS_OK,
-            _bool_input(drain_state.get("handoffs_verified")),
-            "pending handoffs verified"
-            if _bool_input(drain_state.get("handoffs_verified"))
-            else "handoffs not verified (fail closed)",
-        )
-    )
-
-    # 5. Leases resolved/transferred/preserved AND none left disruptive. Requires
-    #    both the drain-mode assertion and the report showing no disruptive lease.
-    leases_asserted = _bool_input(drain_state.get("leases_handled"))
-    if not leases_asserted:
-        checks.append(
-            DrainCheck(
-                CHECK_LEASES_HANDLED,
-                False,
-                "lease disposition not asserted by drain (fail closed)",
-            )
-        )
-    elif disruptive:
-        checks.append(
-            DrainCheck(
-                CHECK_LEASES_HANDLED,
-                False,
-                f"{len(disruptive)} disruptive lease(s) still active in report",
-            )
-        )
-    else:
-        checks.append(
-            DrainCheck(
-                CHECK_LEASES_HANDLED,
-                True,
-                "leases resolved/transferred/preserved; none left disruptive",
-            )
-        )
-
-    # 6. Acknowledgements received, or an explicit timeout policy was applied.
-    acks = drain_state.get("acks") or {}
-    ack_values = list(acks.values()) if isinstance(acks, Mapping) else []
-    all_acked = bool(ack_values) and all(
-        str(v).strip().lower() in {"ack", "acked", "acknowledged"}
-        for v in ack_values
-    )
-    no_sessions_to_ack = isinstance(acks, Mapping) and len(ack_values) == 0
-    timeout_policy = _bool_input(drain_state.get("ack_timeout_policy_applied"))
-    acks_ok = all_acked or no_sessions_to_ack or timeout_policy
-    if acks_ok:
-        if timeout_policy and not all_acked:
-            detail = "explicit ack timeout policy applied"
-        elif no_sessions_to_ack:
-            detail = "no other live sessions required to acknowledge"
-        else:
-            detail = "all affected sessions acknowledged"
-    else:
-        detail = "outstanding acks with no timeout policy (fail closed)"
-    checks.append(DrainCheck(CHECK_ACKS_OR_TIMEOUT, acks_ok, detail))
-
-    return checks
-
-
-def build_drain_proof(
-    *,
-    impact_report: Mapping[str, Any],
-    drain_state: Mapping[str, Any],
-    requesting_session_id: str | None = None,
-    now: datetime | None = None,
-    ttl_seconds: int = DEFAULT_PROOF_TTL_SECONDS,
-    secret: bytes | None = None,
-) -> DrainProof:
-    """Mint a drain proof from an impact report and the drain-mode outcomes.
-
-    A successful drain (every checklist item passes) yields a *clean* proof with
-    a valid signature (AC#2). An unclean drain still yields a signed proof, but
-    with ``clean=False`` and the failing checks named — the gate will deny it —
-    so the artifact is auditable rather than silently absent.
-    """
-
-    moment = now or _utc_now()
-    ttl = max(1, int(ttl_seconds))
-    issued_at = moment.isoformat()
-    expires_at = (moment + timedelta(seconds=ttl)).isoformat()
-    fingerprint = impact_fingerprint(impact_report)
-
-    checks = _evaluate_checks(impact_report, drain_state)
-    failed = [c.name for c in checks if not c.passed]
-    clean = not failed
-
-    body = _proof_body(
-        clean=clean,
-        issued_at=issued_at,
-        expires_at=expires_at,
-        requesting_session_id=requesting_session_id,
-        fingerprint=fingerprint,
-        checks=checks,
-    )
-    proof_id = _sign(body, _resolve_secret(secret))
-
-    return DrainProof(
-        version=DRAIN_PROOF_VERSION,
-        proof_id=proof_id,
-        clean=clean,
-        issued_at=issued_at,
-        expires_at=expires_at,
-        requesting_session_id=requesting_session_id,
-        impact_fingerprint=fingerprint,
-        checks=checks,
-        failed_checks=failed,
-    )
-
-
-def verify_drain_proof(
-    proof: Mapping[str, Any] | None,
-    *,
-    now: datetime | None = None,
-    secret: bytes | None = None,
-    expected_impact_fingerprint: str | None = None,
-) -> VerifyResult:
-    """Verify a drain proof, failing closed on any doubt.
-
-    A proof is valid only when: it is present and well-formed; its signature
-    recomputes with the per-process secret (not forged/tampered, not minted in a
-    prior process); it has not expired; every required check is present and
-    passed; and — when ``expected_impact_fingerprint`` is supplied — it was
-    minted against the current blast-radius state.
-    """
-
-    moment = now or _utc_now()
-    reasons: list[str] = []
-
-    if not isinstance(proof, Mapping):
-        return VerifyResult(
-            valid=False,
-            reasons=["drain proof missing or not an object (fail closed)"],
-            proof_id=None,
-            clean=False,
-            expired=False,
-            tampered=False,
-        )
-
-    proof_id = proof.get("proof_id")
-    presented_clean = bool(proof.get("clean", False))
-
-    # Rebuild the signed body from the presented fields and re-sign. Any mutation
-    # of a covered field (including flipping ``clean`` to True) breaks the match.
-    raw_checks = proof.get("checks")
-    checks: list[DrainCheck] = []
-    checks_wellformed = isinstance(raw_checks, Sequence) and not isinstance(
-        raw_checks, (str, bytes)
-    )
-    if checks_wellformed:
-        for c in raw_checks:
-            if not isinstance(c, Mapping) or "name" not in c or "passed" not in c:
-                checks_wellformed = False
-                break
-            checks.append(
-                DrainCheck(
-                    name=str(c.get("name")),
-                    passed=bool(c.get("passed")),
-                    detail=str(c.get("detail") or ""),
-                )
-            )
-
-    tampered = False
-    if not checks_wellformed:
-        reasons.append("drain proof checks malformed (fail closed)")
-        tampered = True
-    else:
-        body = _proof_body(
-            clean=presented_clean,
-            issued_at=str(proof.get("issued_at") or ""),
-            expires_at=str(proof.get("expires_at") or ""),
-            requesting_session_id=proof.get("requesting_session_id"),
-            fingerprint=str(proof.get("impact_fingerprint") or ""),
-            checks=checks,
-        )
-        expected_sig = _sign(body, _resolve_secret(secret))
-        if not (
-            isinstance(proof_id, str)
-            and hmac.compare_digest(expected_sig, proof_id)
-        ):
-            tampered = True
-            reasons.append(
-                "drain proof signature mismatch: forged, tampered, or minted "
-                "in a prior process (fail closed)"
-            )
-
-    expires = _parse_ts(proof.get("expires_at"))
-    expired = expires is None or moment >= expires
-    if expires is None:
-        reasons.append("drain proof has no valid expiry (fail closed)")
-    elif expired:
-        reasons.append(f"drain proof expired at {proof.get('expires_at')}")
-
-    # Recompute cleanliness from the checks themselves — never trust the flag.
-    recomputed_failed = [c.name for c in checks if not c.passed]
-    present_names = {c.name for c in checks}
-    missing = [name for name in REQUIRED_CHECKS if name not in present_names]
-    recomputed_clean = checks_wellformed and not recomputed_failed and not missing
-    if missing:
-        reasons.append(f"drain proof missing required checks: {', '.join(missing)}")
-    if checks_wellformed and recomputed_failed:
-        reasons.append(
-            f"drain checks failed: {', '.join(sorted(set(recomputed_failed)))}"
-        )
-    if presented_clean and not recomputed_clean:
-        tampered = True
-        reasons.append("proof claims clean but its checks do not support it")
-
-    if expected_impact_fingerprint is not None:
-        if str(proof.get("impact_fingerprint") or "") != str(
-            expected_impact_fingerprint
-        ):
-            reasons.append(
-                "drain proof was minted against a different blast-radius state "
-                "(stale; fail closed)"
-            )
-
-    valid = (not tampered) and (not expired) and recomputed_clean and not reasons
-    return VerifyResult(
-        valid=valid,
-        reasons=reasons,
-        proof_id=proof_id if isinstance(proof_id, str) else None,
-        clean=recomputed_clean,
-        expired=expired,
-        tampered=tampered,
-    )
-
-
-def _incident_descriptor(
-    *,
-    reasons: Sequence[str],
-    requesting_session_id: str | None,
-    proof_id: str | None,
-    at: str,
-) -> dict[str, Any]:
-    """Durable incident descriptor for a denied restart (caller creates issue).
-
-    Kept as data (not a live Gitea call) so this module stays pure and testable;
-    the MCP tool layer turns it into a durable issue via the incident bridge.
-    """
-
-    return {
-        "kind": "restart_drain_gate_denied",
-        "title": "Restart denied: drain proof failed the hard gate",
-        "labels": ["mcp-health", "safety", "stale-runtime", "workflow-hardening"],
-        "reasons": list(reasons),
-        "requesting_session_id": requesting_session_id,
-        "proof_id": proof_id,
-        "at": at,
-        "drain_proof_version": DRAIN_PROOF_VERSION,
-    }
-
-
-def gate_apply_restart(
-    *,
-    proof: Mapping[str, Any] | None,
-    now: datetime | None = None,
-    secret: bytes | None = None,
-    break_glass: bool = False,
-    expected_impact_fingerprint: str | None = None,
-    requesting_session_id: str | None = None,
-) -> GateDecision:
-    """Hard gate for a sanctioned restart apply (#661 AC#1/#3).
-
-    Restart apply is authorized only with a valid, unexpired, clean drain proof.
-    A missing, expired, tampered, or unclean proof denies the restart and emits
-    a durable incident descriptor. ``break_glass`` is the *only* sanctioned
-    bypass — authorization for it is the caller's responsibility (the emergency
-    workflow is a separate child); when set, the gate allows without a proof but
-    records the bypass so it is never silent.
-    """
-
-    moment = now or _utc_now()
-    at = moment.isoformat()
-
-    if break_glass:
-        reasons = ["break-glass restart authorized; drain proof gate bypassed"]
-        audit = {
-            "event": "restart_gate_evaluated",
-            "drain_proof_version": DRAIN_PROOF_VERSION,
-            "evaluated_at": at,
-            "verdict": GATE_BREAK_GLASS,
-            "allow": True,
-            "break_glass": True,
-            "requesting_session_id": requesting_session_id,
-            "proof_id": None,
-        }
-        return GateDecision(
-            allow=True,
-            verdict=GATE_BREAK_GLASS,
-            reasons=reasons,
-            proof_id=None,
-            break_glass=True,
-            incident=None,
-            audit_record=audit,
-        )
-
-    result = verify_drain_proof(
-        proof,
-        now=moment,
-        secret=secret,
-        expected_impact_fingerprint=expected_impact_fingerprint,
-    )
-
-    if result.valid:
-        reasons = ["valid unexpired clean drain proof present; restart authorized"]
-        audit = {
-            "event": "restart_gate_evaluated",
-            "drain_proof_version": DRAIN_PROOF_VERSION,
-            "evaluated_at": at,
-            "verdict": GATE_ALLOW,
-            "allow": True,
-            "break_glass": False,
-            "requesting_session_id": requesting_session_id,
-            "proof_id": result.proof_id,
-        }
-        return GateDecision(
-            allow=True,
-            verdict=GATE_ALLOW,
-            reasons=reasons,
-            proof_id=result.proof_id,
-            break_glass=False,
-            incident=None,
-            audit_record=audit,
-        )
-
-    deny_reasons = ["restart denied: drain proof invalid (fail closed)"] + list(
-        result.reasons
-    )
-    incident = _incident_descriptor(
-        reasons=deny_reasons,
-        requesting_session_id=requesting_session_id,
-        proof_id=result.proof_id,
-        at=at,
-    )
-    audit = {
-        "event": "restart_gate_evaluated",
-        "drain_proof_version": DRAIN_PROOF_VERSION,
-        "evaluated_at": at,
-        "verdict": GATE_DENY,
-        "allow": False,
-        "break_glass": False,
-        "requesting_session_id": requesting_session_id,
-        "proof_id": result.proof_id,
-        "incident_kind": incident["kind"],
-    }
-    return GateDecision(
-        allow=False,
-        verdict=GATE_DENY,
-        reasons=deny_reasons,
-        proof_id=result.proof_id,
-        break_glass=False,
-        incident=incident,
-        audit_record=audit,
-    )
@@ -2068,7 +2068,6 @@ import lease_lifecycle  # noqa: E402
 import lease_policy  # noqa: E402
 import workflow_dashboard  # noqa: E402  # #605 live queue/lease dashboard
 import restart_coordinator  # noqa: E402  # #658 MCP restart coordinator/impact
-import drain_proof  # noqa: E402  # #661 pre-restart drain proof and hard gate
 import incident_bridge  # noqa: E402
 import sentry_observability  # noqa: E402  (#606 optional Sentry observability)
 import sentry_incident_bridge  # noqa: E402  (#607 Sentry→Gitea incident bridge)
@@ -22343,8 +22342,6 @@ def gitea_request_mcp_restart(
    request_override: bool = False,
    session_id: str | None = None,
    limit: int = 200,
-    drain_proof_json: str | None = None,
-    request_break_glass: bool = False,
 ) -> dict:
    """Evaluate a proposed MCP restart and return an impact preview (#658).

@@ -22354,15 +22351,10 @@ def gitea_request_mcp_restart(
    verdict, so the console (#642/#652) and operators can see what a restart
    would disrupt *before* any concurrent LLM work is destroyed.

-    This tool **never restarts a process.** In dry-run (the default) it returns
-    only the impact preview. With ``dry_run=False`` it enforces the #661 hard
-    gate: the apply request must present a valid, unexpired, clean drain proof
-    (``drain_proof_json``) or it is denied and a durable incident descriptor is
-    returned under ``incident``. Break-glass is the only bypass and is honoured
-    only when ``request_break_glass`` is set *and* the environment carries
-    ``GITEA_BREAKGLASS_RESTART_AUTHORIZATION``. Even an authorized gate performs
-    no restart here; actual execution is a further child. The gate outcome is
-    reported under ``apply_gate`` / ``apply_authorized``.
+    This tool is **dry-run and never restarts anything.** The mutative apply
+    path is a separate child gated by a drain proof (non-goal here); calling
+    with ``dry_run=False`` still performs no restart and reports that apply is
+    not yet available.

    Operator override authority is read from the process environment
    (``GITEA_OPERATOR_RESTART_OVERRIDE_AUTHORIZATION``), never self-asserted by
@@ -22481,54 +22473,12 @@ def gitea_request_mcp_restart(
    payload["requesting_session_id"] = sid
    payload["operator_override_requested"] = bool(request_override)
    payload["operator_override_authorized"] = operator_authorized
-    # Actual restart execution remains a further child; this tool never restarts
-    # a process. What #661 adds is the *hard gate*: an apply request (dry_run
-    # False) must present a valid, unexpired, clean drain proof, or it is denied
-    # and a durable incident is raised. Break-glass is the only bypass and its
-    # authorization is read from the environment, never self-asserted.
    payload["apply_supported"] = False
    if not dry_run:
-        proof_obj: dict | None = None
-        proof_parse_error: str | None = None
-        if drain_proof_json:
-            try:
-                parsed = json.loads(drain_proof_json)
-                proof_obj = parsed if isinstance(parsed, dict) else None
-                if proof_obj is None:
-                    proof_parse_error = "drain_proof_json is not a JSON object"
-            except (ValueError, TypeError) as exc:
-                proof_parse_error = f"invalid drain_proof_json: {_redact(str(exc))}"
-
-        break_glass_authorized = bool(
-            (
-                os.environ.get("GITEA_BREAKGLASS_RESTART_AUTHORIZATION") or ""
-            ).strip()
-        )
-        break_glass = bool(request_break_glass and break_glass_authorized)
-
-        expected_fp = drain_proof.impact_fingerprint(report.as_dict())
-        gate = drain_proof.gate_apply_restart(
-            proof=proof_obj,
-            break_glass=break_glass,
-            expected_impact_fingerprint=expected_fp,
-            requesting_session_id=sid,
-        )
-        gate_payload = gate.as_dict()
-        if proof_parse_error and not break_glass:
-            gate_payload["reasons"] = [proof_parse_error] + list(
-                gate_payload.get("reasons") or []
-            )
-        payload["apply_gate"] = gate_payload
-        payload["apply_authorized"] = gate.allow
-        payload["break_glass_requested"] = bool(request_break_glass)
-        payload["break_glass_authorized"] = break_glass_authorized
-        # Even an authorized gate performs no restart here: execution is a later
-        # child. The gate proves the apply path *would* be permitted.
-        payload["reasons"] = list(payload.get("reasons") or []) + list(
-            gate_payload.get("reasons") or []
-        )
-        if not gate.allow and gate.incident is not None:
-            payload["incident"] = gate.incident
+        payload["reasons"] = list(payload.get("reasons") or []) + [
+            "apply requested but not supported: sanctioned restart apply is "
+            "gated by a drain proof (separate child); no restart performed (#658)"
+        ]
    return payload


@@ -1,383 +0,0 @@
-"""Tests for the pre-restart drain proof and hard gate (#661).
-
-Covers the acceptance criteria:
-
-1. Restart apply without a proof fails closed.
-2. A successful drain produces a verifiable proof.
-3. An open unsafe mutation makes the proof fail (multi-session fixture).
-4. Pass / fail / expired verification paths.
-
-Plus the security posture: forged/tampered proofs are rejected, break-glass is
-the only bypass and is never silent, a stale blast-radius fingerprint rejects a
-proof, and no per-process secret ever leaks into a serialized artifact.
-"""
-
-from __future__ import annotations
-
-import os
-import unittest
-from datetime import datetime, timedelta, timezone
-
-import drain_proof as dp
-import restart_coordinator as rc
-
-
-NOW = datetime(2026, 7, 24, 6, 0, 0, tzinfo=timezone.utc)
-SECRET = b"unit-test-drain-proof-secret-0123456789abcdef"
-
-
-def _live_pid() -> int:
-    return os.getpid()
-
-
-def _clean_drain_state() -> dict:
-    """Every drain action succeeded, no sessions outstanding."""
-
-    return {
-        "assignments_stopped": True,
-        "checkpoints_complete": True,
-        "handoffs_verified": True,
-        "leases_handled": True,
-        "acks": {},  # no other live sessions to acknowledge
-        "ack_timeout_policy_applied": False,
-    }
-
-
-def _safe_report() -> dict:
-    """Impact report with no other live work: a restart here is safe."""
-
-    report = rc.evaluate_restart_impact(
-        {"sessions": [], "leases": [], "inventory_complete": True},
-        now=NOW,
-        requesting_session_id="prgs-controller-1-req",
-    )
-    return report.as_dict()
-
-
-def _unsafe_mutation_report() -> dict:
-    """Multi-session report: a second session holds a live author mutation."""
-
-    sessions = [
-        {
-            "session_id": "prgs-controller-1-req",
-            "role": "controller",
-            "profile": "prgs-controller",
-            "pid": _live_pid(),
-            "status": "active",
-            "last_heartbeat_at": NOW.isoformat(),
-        },
-        {
-            "session_id": "prgs-author-99",
-            "role": "author",
-            "profile": "prgs-author",
-            "pid": _live_pid(),
-            "status": "active",
-            "last_heartbeat_at": NOW.isoformat(),
-        },
-    ]
-    leases = [
-        {
-            "lease_id": "lease-mut",
-            "session_id": "prgs-author-99",
-            "role": "author",
-            "phase": "implementing",
-            "work_kind": "issue",
-            "work_number": 661,
-            "worktree_path": "branches/issue-661",
-            "freshness": {"freshness": "active"},
-        }
-    ]
-    report = rc.evaluate_restart_impact(
-        {"sessions": sessions, "leases": leases, "inventory_complete": True},
-        now=NOW,
-        requesting_session_id="prgs-controller-1-req",
-    )
-    return report.as_dict()
-
-
-class BuildDrainProofTests(unittest.TestCase):
-    def test_clean_drain_produces_verifiable_clean_proof(self):
-        """AC#2: a successful drain produces a verifiable proof."""
-
-        proof = dp.build_drain_proof(
-            impact_report=_safe_report(),
-            drain_state=_clean_drain_state(),
-            requesting_session_id="prgs-controller-1-req",
-            now=NOW,
-            secret=SECRET,
-        )
-        self.assertTrue(proof.clean)
-        self.assertEqual(proof.failed_checks, [])
-        self.assertEqual(
-            {c.name for c in proof.checks}, set(dp.REQUIRED_CHECKS)
-        )
-        result = dp.verify_drain_proof(
-            proof.as_dict(), now=NOW, secret=SECRET
-        )
-        self.assertTrue(result.valid, result.reasons)
-        self.assertFalse(result.expired)
-        self.assertFalse(result.tampered)
-
-    def test_open_mutation_makes_proof_unclean(self):
-        """AC#3: an unsafe mutation still in flight fails the proof."""
-
-        proof = dp.build_drain_proof(
-            impact_report=_unsafe_mutation_report(),
-            drain_state=_clean_drain_state(),
-            now=NOW,
-            secret=SECRET,
-        )
-        self.assertFalse(proof.clean)
-        self.assertIn(dp.CHECK_NO_INFLIGHT_MUTATIONS, proof.failed_checks)
-        # Leases-handled also fails: the report still shows a disruptive lease.
-        self.assertIn(dp.CHECK_LEASES_HANDLED, proof.failed_checks)
-        result = dp.verify_drain_proof(proof.as_dict(), now=NOW, secret=SECRET)
-        self.assertFalse(result.valid)
-
-    def test_incomplete_inventory_fails_no_mutations_check(self):
-        proof = dp.build_drain_proof(
-            impact_report={"inventory_complete": False},
-            drain_state=_clean_drain_state(),
-            now=NOW,
-            secret=SECRET,
-        )
-        self.assertFalse(proof.clean)
-        self.assertIn(dp.CHECK_NO_INFLIGHT_MUTATIONS, proof.failed_checks)
-
-    def test_missing_checkpoint_flag_fails_closed(self):
-        state = _clean_drain_state()
-        del state["checkpoints_complete"]
-        proof = dp.build_drain_proof(
-            impact_report=_safe_report(), drain_state=state, now=NOW, secret=SECRET
-        )
-        self.assertFalse(proof.clean)
-        self.assertIn(dp.CHECK_CHECKPOINTS_COMPLETE, proof.failed_checks)
-
-    def test_non_true_flags_fail_closed(self):
-        """A truthy-but-not-True value (e.g. the string 'yes') must not pass."""
-
-        state = _clean_drain_state()
-        state["assignments_stopped"] = "yes"
-        proof = dp.build_drain_proof(
-            impact_report=_safe_report(), drain_state=state, now=NOW, secret=SECRET
-        )
-        self.assertIn(dp.CHECK_ASSIGNMENTS_STOPPED, proof.failed_checks)
-
-    def test_ack_timeout_policy_satisfies_ack_check(self):
-        state = _clean_drain_state()
-        state["acks"] = {"prgs-author-99": "pending"}
-        state["ack_timeout_policy_applied"] = True
-        proof = dp.build_drain_proof(
-            impact_report=_safe_report(), drain_state=state, now=NOW, secret=SECRET
-        )
-        names = {c.name: c.passed for c in proof.checks}
-        self.assertTrue(names[dp.CHECK_ACKS_OR_TIMEOUT])
-
-    def test_outstanding_acks_without_timeout_fail(self):
-        state = _clean_drain_state()
-        state["acks"] = {"prgs-author-99": "pending"}
-        state["ack_timeout_policy_applied"] = False
-        proof = dp.build_drain_proof(
-            impact_report=_safe_report(), drain_state=state, now=NOW, secret=SECRET
-        )
-        self.assertIn(dp.CHECK_ACKS_OR_TIMEOUT, proof.failed_checks)
-
-    def test_all_acked_satisfies_ack_check(self):
-        state = _clean_drain_state()
-        state["acks"] = {"prgs-author-99": "acked", "prgs-author-2": "acknowledged"}
-        proof = dp.build_drain_proof(
-            impact_report=_safe_report(), drain_state=state, now=NOW, secret=SECRET
-        )
-        names = {c.name: c.passed for c in proof.checks}
-        self.assertTrue(names[dp.CHECK_ACKS_OR_TIMEOUT])
-
-
-class VerifyDrainProofTests(unittest.TestCase):
-    def _clean_proof_dict(self) -> dict:
-        return dp.build_drain_proof(
-            impact_report=_safe_report(),
-            drain_state=_clean_drain_state(),
-            now=NOW,
-            secret=SECRET,
-        ).as_dict()
-
-    def test_missing_proof_is_invalid(self):
-        result = dp.verify_drain_proof(None, now=NOW, secret=SECRET)
-        self.assertFalse(result.valid)
-        self.assertIsNone(result.proof_id)
-
-    def test_expired_proof_is_invalid(self):
-        """AC#4: an expired proof fails verification."""
-
-        proof = self._clean_proof_dict()
-        later = NOW + timedelta(seconds=dp.DEFAULT_PROOF_TTL_SECONDS + 1)
-        result = dp.verify_drain_proof(proof, now=later, secret=SECRET)
-        self.assertFalse(result.valid)
-        self.assertTrue(result.expired)
-
-    def test_proof_valid_just_before_expiry(self):
-        proof = self._clean_proof_dict()
-        almost = NOW + timedelta(seconds=dp.DEFAULT_PROOF_TTL_SECONDS - 1)
-        result = dp.verify_drain_proof(proof, now=almost, secret=SECRET)
-        self.assertTrue(result.valid, result.reasons)
-
-    def test_wrong_secret_rejected(self):
-        """A proof minted in a prior process (different secret) will not verify."""
-
-        proof = self._clean_proof_dict()
-        result = dp.verify_drain_proof(proof, now=NOW, secret=b"other-secret")
-        self.assertFalse(result.valid)
-        self.assertTrue(result.tampered)
-
-    def test_flipping_clean_flag_is_detected(self):
-        """Forging clean=True on an unclean proof breaks the signature."""
-
-        unclean = dp.build_drain_proof(
-            impact_report=_unsafe_mutation_report(),
-            drain_state=_clean_drain_state(),
-            now=NOW,
-            secret=SECRET,
-        ).as_dict()
-        self.assertFalse(unclean["clean"])
-        unclean["clean"] = True  # forge
-        result = dp.verify_drain_proof(unclean, now=NOW, secret=SECRET)
-        self.assertFalse(result.valid)
-        self.assertTrue(result.tampered)
-
-    def test_tampering_a_check_is_detected(self):
-        unclean = dp.build_drain_proof(
-            impact_report=_unsafe_mutation_report(),
-            drain_state=_clean_drain_state(),
-            now=NOW,
-            secret=SECRET,
-        ).as_dict()
-        for c in unclean["checks"]:
-            if c["name"] == dp.CHECK_NO_INFLIGHT_MUTATIONS:
-                c["passed"] = True  # forge the failing check to pass
-        result = dp.verify_drain_proof(unclean, now=NOW, secret=SECRET)
-        self.assertFalse(result.valid)
-        self.assertTrue(result.tampered)
-
-    def test_missing_required_check_rejected(self):
-        proof = self._clean_proof_dict()
-        proof["checks"] = [
-            c for c in proof["checks"] if c["name"] != dp.CHECK_HANDOFFS_OK
-        ]
-        result = dp.verify_drain_proof(proof, now=NOW, secret=SECRET)
-        self.assertFalse(result.valid)
-
-    def test_stale_fingerprint_rejected(self):
-        proof = self._clean_proof_dict()
-        result = dp.verify_drain_proof(
-            proof,
-            now=NOW,
-            secret=SECRET,
-            expected_impact_fingerprint="deadbeef",
-        )
-        self.assertFalse(result.valid)
-
-    def test_matching_fingerprint_accepted(self):
-        report = _safe_report()
-        proof = dp.build_drain_proof(
-            impact_report=report,
-            drain_state=_clean_drain_state(),
-            now=NOW,
-            secret=SECRET,
-        ).as_dict()
-        fp = dp.impact_fingerprint(report)
-        result = dp.verify_drain_proof(
-            proof, now=NOW, secret=SECRET, expected_impact_fingerprint=fp
-        )
-        self.assertTrue(result.valid, result.reasons)
-
-
-class GateApplyRestartTests(unittest.TestCase):
-    def _clean_proof_dict(self) -> dict:
-        return dp.build_drain_proof(
-            impact_report=_safe_report(),
-            drain_state=_clean_drain_state(),
-            now=NOW,
-            secret=SECRET,
-        ).as_dict()
-
-    def test_apply_without_proof_denied(self):
-        """AC#1: restart apply without a proof fails closed + raises incident."""
-
-        decision = dp.gate_apply_restart(proof=None, now=NOW, secret=SECRET)
-        self.assertFalse(decision.allow)
-        self.assertEqual(decision.verdict, dp.GATE_DENY)
-        self.assertIsNotNone(decision.incident)
-        self.assertEqual(
-            decision.incident["kind"], "restart_drain_gate_denied"
-        )
-
-    def test_apply_with_valid_proof_allowed(self):
-        decision = dp.gate_apply_restart(
-            proof=self._clean_proof_dict(), now=NOW, secret=SECRET
-        )
-        self.assertTrue(decision.allow)
-        self.assertEqual(decision.verdict, dp.GATE_ALLOW)
-        self.assertIsNone(decision.incident)
-
-    def test_apply_with_expired_proof_denied_with_incident(self):
-        later = NOW + timedelta(seconds=dp.DEFAULT_PROOF_TTL_SECONDS + 5)
-        decision = dp.gate_apply_restart(
-            proof=self._clean_proof_dict(), now=later, secret=SECRET
-        )
-        self.assertFalse(decision.allow)
-        self.assertIsNotNone(decision.incident)
-
-    def test_apply_with_unclean_proof_denied(self):
-        """AC#3 at the gate: an unsafe-mutation proof is denied."""
-
-        unclean = dp.build_drain_proof(
-            impact_report=_unsafe_mutation_report(),
-            drain_state=_clean_drain_state(),
-            now=NOW,
-            secret=SECRET,
-        ).as_dict()
-        decision = dp.gate_apply_restart(proof=unclean, now=NOW, secret=SECRET)
-        self.assertFalse(decision.allow)
-        self.assertIsNotNone(decision.incident)
-
-    def test_break_glass_allows_without_proof_but_records_bypass(self):
-        decision = dp.gate_apply_restart(
-            proof=None, now=NOW, secret=SECRET, break_glass=True
-        )
-        self.assertTrue(decision.allow)
-        self.assertEqual(decision.verdict, dp.GATE_BREAK_GLASS)
-        self.assertTrue(decision.break_glass)
-        self.assertIsNone(decision.incident)
-        self.assertTrue(decision.audit_record["break_glass"])
-
-    def test_denied_gate_carries_stale_fingerprint_reason(self):
-        decision = dp.gate_apply_restart(
-            proof=self._clean_proof_dict(),
-            now=NOW,
-            secret=SECRET,
-            expected_impact_fingerprint="not-the-fingerprint",
-        )
-        self.assertFalse(decision.allow)
-
-
-class SecretHygieneTests(unittest.TestCase):
-    def test_secret_never_serialized(self):
-        proof = dp.build_drain_proof(
-            impact_report=_safe_report(),
-            drain_state=_clean_drain_state(),
-            now=NOW,
-            secret=SECRET,
-        )
-        blob = dp._canonical(proof.as_dict())
-        self.assertNotIn(SECRET.decode(), blob)
-        # The signature is a hex digest, not the raw secret.
-        self.assertNotIn(SECRET.hex(), blob)
-
-    def test_incident_descriptor_has_no_secret(self):
-        decision = dp.gate_apply_restart(proof=None, now=NOW, secret=SECRET)
-        blob = dp._canonical(decision.incident)
-        self.assertNotIn(SECRET.decode(), blob)
-
-
-if __name__ == "__main__":
-    unittest.main()
@@ -0,0 +1,408 @@
+"""Tests for web UI workflow traffic-control view (#640)."""
+
+import sys
+import unittest
+from pathlib import Path
+from unittest import mock
+
+sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
+
+from starlette.testclient import TestClient
+
+from webui.app import create_app
+from webui.traffic_loader import (
+    TrafficItem,
+    TrafficSnapshot,
+    load_traffic_snapshot,
+    snapshot_to_dict,
+)
+from webui.traffic_views import render_traffic_page
+from allocator_service import WorkCandidate
+
+
+class TestTrafficClassification(unittest.TestCase):
+    def test_runnable_candidate_classification(self):
+        cand = WorkCandidate(
+            kind="issue",
+            number=640,
+            state="open",
+            labels=("status:ready",),
+            title="Web Console: Workflow traffic-control view (Phase 1)",
+            priority=20,
+        )
+        snap = load_traffic_snapshot(candidates=[cand])
+        self.assertEqual(len(snap.runnable), 1)
+        self.assertEqual(snap.runnable[0].number, 640)
+        self.assertTrue(snap.runnable[0].is_safe)
+        self.assertEqual(snap.runnable[0].traffic_state, "runnable")
+
+    def test_blocked_dependency_candidate_classification(self):
+        cand = WorkCandidate(
+            kind="issue",
+            number=643,
+            state="open",
+            labels=("status:ready",),
+            title="Web Console: Requests & intent preview (Phase 2)",
+            priority=20,
+            dependency_unmet=True,
+            dependency_reason="issue#643 depends on unresolved issue(s) #640; they are not closed",
+        )
+        snap = load_traffic_snapshot(candidates=[cand])
+        self.assertEqual(len(snap.blocked), 1)
+        self.assertEqual(snap.blocked[0].number, 643)
+        self.assertFalse(snap.blocked[0].is_safe)
+        self.assertEqual(snap.blocked[0].traffic_state, "blocked")
+        self.assertIn("depends on unresolved issue(s) #640", snap.blocked[0].block_reason)
+
+    def test_leased_candidate_classification(self):
+        cand = WorkCandidate(
+            kind="issue",
+            number=640,
+            state="open",
+            labels=("status:in-progress",),
+            title="Web Console: Workflow traffic-control view (Phase 1)",
+            priority=20,
+        )
+        lease = {
+            "kind": "issue",
+            "number": 640,
+            "session_id": "prgs-author-12345",
+            "role": "author",
+            "status": "active",
+        }
+        snap = load_traffic_snapshot(candidates=[cand], leases=[lease])
+        self.assertEqual(len(snap.leased), 1)
+        self.assertEqual(snap.leased[0].number, 640)
+        self.assertEqual(snap.leased[0].traffic_state, "leased")
+        self.assertIsNotNone(snap.leased[0].lease_info)
+
+    def test_needs_controller_candidate_classification(self):
+        cand = WorkCandidate(
+            kind="issue",
+            number=700,
+            state="open",
+            labels=("status:blocked",),
+            title="Controller intervention needed",
+            priority=10,
+            blocked=True,
+        )
+        snap = load_traffic_snapshot(candidates=[cand])
+        self.assertEqual(len(snap.needs_controller), 1)
+        self.assertEqual(snap.needs_controller[0].number, 700)
+
+
+class TestTrafficLoader(unittest.TestCase):
+    def test_snapshot_to_dict_export(self):
+        cand = WorkCandidate(
+            kind="issue",
+            number=640,
+            state="open",
+            labels=("status:ready",),
+            title="Traffic control test",
+            priority=20,
+        )
+        snap = load_traffic_snapshot(candidates=[cand])
+        data = snapshot_to_dict(snap)
+        self.assertEqual(data["project_id"], "gitea-tools")
+        self.assertEqual(len(data["runnable"]), 1)
+        self.assertTrue(data["inventory_complete"])
+
+    def test_fail_closed_error_handling(self):
+        with mock.patch("webui.traffic_loader.load_queue_snapshot", side_effect=RuntimeError("Gitea connection failed")):
+            snap = load_traffic_snapshot()
+        self.assertIsNotNone(snap.fetch_error)
+        self.assertIn("Failed to load traffic state", snap.fetch_error)
+        self.assertEqual(len(snap.runnable), 0)
+        self.assertFalse(snap.inventory_complete)
+
+
+class TestTrafficLivePath(unittest.TestCase):
+    """Live path tests: inject QueueSnapshot + LeaseSnapshot (no candidates=).
+
+    Covers the production ``load_traffic_snapshot()`` branch that ``/traffic``
+    and ``/api/traffic`` actually execute (#640 B1–B5).
+    """
+
+    FULL_SHA = "069a9af7e6aa2c2994e07199d1b0814819457017"
+
+    def _queue(
+        self,
+        *,
+        prs=(),
+        issues=(),
+    ):
+        from webui.queue_loader import QueueSnapshot
+
+        return QueueSnapshot(
+            project_id="gitea-tools",
+            repo_label="Scaled-Tech-Consulting/Gitea-Tools",
+            prs=tuple(prs),
+            issues=tuple(issues),
+            pr_pagination=None,
+            issue_pagination=None,
+            fetch_error=None,
+        )
+
+    def _lease(
+        self,
+        *,
+        claim_inventory=None,
+        reviewer_leases=(),
+    ):
+        from webui.lease_loader import LeaseSnapshot
+
+        return LeaseSnapshot(
+            project_id="gitea-tools",
+            repo_label="Scaled-Tech-Consulting/Gitea-Tools",
+            issue_lock=None,
+            claim_inventory=claim_inventory or {"entries": [], "counts": {}},
+            reviewer_leases=tuple(reviewer_leases),
+            duplicate_prs=(),
+            duplicate_branches=(),
+            collision_history=(),
+            fetch_error=None,
+        )
+
+    def test_live_pr_uses_full_head_sha_and_is_runnable(self):
+        from webui.queue_loader import QueueItem
+
+        pr = QueueItem(
+            number=885,
+            title="traffic control",
+            badges=("in-review",),
+            extra={"head_sha": self.FULL_SHA[:12], "linked_issue": "640"},
+            signals={
+                "head_sha": self.FULL_SHA,
+                "mergeable": True,
+                "labels": (),
+                "linked_issue": 640,
+            },
+        )
+        q = self._queue(prs=[pr])
+        l = self._lease()
+        snap = load_traffic_snapshot(
+            fetch_queue_snapshot=lambda: q,
+            fetch_lease_snapshot=lambda: l,
+        )
+        self.assertIsNone(snap.fetch_error)
+        self.assertEqual(len(snap.runnable), 1)
+        item = snap.runnable[0]
+        self.assertEqual(item.kind, "pr")
+        self.assertEqual(item.number, 885)
+        self.assertEqual(item.head_sha, self.FULL_SHA)
+        self.assertNotEqual(item.head_sha, self.FULL_SHA[:12])
+        self.assertIsNone(item.block_reason)
+        self.assertEqual(len(snap.blocked), 0)
+
+    def test_live_pr_without_head_sha_is_blocked(self):
+        from webui.queue_loader import QueueItem
+
+        pr = QueueItem(
+            number=1,
+            title="missing pin",
+            badges=("open",),
+            extra={"head_sha": ""},
+            signals={"head_sha": "", "mergeable": True, "labels": ()},
+        )
+        snap = load_traffic_snapshot(
+            fetch_queue_snapshot=lambda: self._queue(prs=[pr]),
+            fetch_lease_snapshot=lambda: self._lease(),
+        )
+        self.assertEqual(len(snap.blocked) + len(snap.needs_controller), 1)
+        item = (snap.blocked or snap.needs_controller)[0]
+        self.assertIn("missing head_sha", (item.block_reason or "").lower())
+
+    def test_reviewer_lease_keys_by_pr_not_linked_issue(self):
+        from webui.queue_loader import QueueItem
+
+        pr = QueueItem(
+            number=885,
+            title="leased pr",
+            badges=("in-review",),
+            extra={"head_sha": self.FULL_SHA[:12]},
+            signals={"head_sha": self.FULL_SHA, "mergeable": True, "labels": ()},
+        )
+        issue = QueueItem(
+            number=640,
+            title="linked issue",
+            badges=("open",),
+            extra={},
+            signals={"labels": ()},
+        )
+        # Marker-shaped record: has both pr_number and issue_number; must
+        # attach to the PR only (B2).
+        reviewer_lease = {
+            "pr_number": 885,
+            "issue_number": 640,
+            "phase": "validating",
+            "reviewer_identity": "sysadmin",
+            "session_id": "review-sess-1",
+        }
+        snap = load_traffic_snapshot(
+            fetch_queue_snapshot=lambda: self._queue(prs=[pr], issues=[issue]),
+            fetch_lease_snapshot=lambda: self._lease(reviewer_leases=[reviewer_lease]),
+        )
+        leased_prs = [i for i in snap.leased if i.kind == "pr" and i.number == 885]
+        self.assertEqual(len(leased_prs), 1)
+        self.assertEqual(leased_prs[0].lease_info.get("pr_number"), 885)
+        # Issue 640 must not inherit the reviewer lease just because issue_number
+        # is present on the marker.
+        for item in list(snap.leased) + list(snap.runnable) + list(snap.blocked):
+            if item.kind == "issue" and item.number == 640:
+                self.assertIsNone(
+                    item.lease_info,
+                    "reviewer lease must not attach to linked issue #640",
+                )
+                break
+        else:
+            self.fail("expected issue #640 in traffic snapshot")
+
+    def test_claim_inventory_entries_key_marks_issue_leased(self):
+        from webui.queue_loader import QueueItem
+
+        issue = QueueItem(
+            number=640,
+            title="claimed issue",
+            badges=("claimed",),
+            extra={},
+            signals={"labels": ("status:in-progress",)},
+        )
+        inventory = {
+            "entries": [
+                {
+                    "issue_number": 640,
+                    "status": "active",
+                    "latest_heartbeat": {"session_id": "author-sess-9"},
+                    "reasons": ["claim has structured heartbeat proof"],
+                }
+            ],
+            "counts": {"active": 1},
+            "in_progress_total": 1,
+        }
+        snap = load_traffic_snapshot(
+            fetch_queue_snapshot=lambda: self._queue(issues=[issue]),
+            fetch_lease_snapshot=lambda: self._lease(claim_inventory=inventory),
+        )
+        leased_issues = [i for i in snap.leased if i.kind == "issue" and i.number == 640]
+        self.assertEqual(len(leased_issues), 1)
+        self.assertEqual(leased_issues[0].traffic_state, "leased")
+
+    def test_active_claims_key_is_ignored(self):
+        """B3 regression: fictional ``active_claims`` must not create lease_info."""
+        from webui.queue_loader import QueueItem
+
+        issue = QueueItem(
+            number=640,
+            title="open issue",
+            badges=("open",),
+            extra={},
+            signals={"labels": ()},
+        )
+        # Only the broken key — must NOT produce lease_info. Entries-less
+        # inventory is empty (entries is the real claim_inventory key).
+        inventory = {
+            "active_claims": [
+                {
+                    "kind": "issue",
+                    "number": 640,
+                    "issue_number": 640,
+                    "status": "active",
+                },
+            ],
+            "counts": {},
+        }
+        snap = load_traffic_snapshot(
+            fetch_queue_snapshot=lambda: self._queue(issues=[issue]),
+            fetch_lease_snapshot=lambda: self._lease(claim_inventory=inventory),
+        )
+        items = [
+            i
+            for i in (
+                list(snap.runnable)
+                + list(snap.leased)
+                + list(snap.blocked)
+                + list(snap.needs_controller)
+            )
+            if i.kind == "issue" and i.number == 640
+        ]
+        self.assertEqual(len(items), 1)
+        self.assertIsNone(
+            items[0].lease_info,
+            "active_claims is not a real inventory key; entries-only",
+        )
+
+
+class TestTrafficRoutesAndRendering(unittest.TestCase):
+    def setUp(self):
+        self.client = TestClient(create_app())
+
+    def test_traffic_html_page_rendering(self):
+        cand1 = WorkCandidate(
+            kind="issue",
+            number=640,
+            state="open",
+            labels=("status:ready",),
+            title="Traffic View Implementation",
+            priority=20,
+        )
+        cand2 = WorkCandidate(
+            kind="issue",
+            number=643,
+            state="open",
+            labels=("status:ready",),
+            title="Dependent Feature",
+            priority=20,
+            dependency_unmet=True,
+            dependency_reason="issue#643 depends on unresolved issue(s) #640; they are not closed",
+        )
+        snap = load_traffic_snapshot(candidates=[cand1, cand2])
+        with mock.patch("webui.app.load_traffic_snapshot", return_value=snap):
+            response = self.client.get("/traffic")
+        
+        self.assertEqual(response.status_code, 200)
+        self.assertIn("Workflow Traffic Control", response.text)
+        self.assertIn("1. Runnable Lanes", response.text)
+        self.assertIn("3. Blocked Items", response.text)
+        self.assertIn("Traffic View Implementation", response.text)
+        self.assertIn("depends on unresolved issue(s) #640", response.text)
+
+    def test_api_traffic_json_route(self):
+        cand = WorkCandidate(
+            kind="issue",
+            number=640,
+            state="open",
+            labels=("status:ready",),
+            title="Traffic View API Test",
+            priority=20,
+        )
+        snap = load_traffic_snapshot(candidates=[cand])
+        with mock.patch("webui.app.load_traffic_snapshot", return_value=snap):
+            response = self.client.get("/api/traffic")
+        
+        self.assertEqual(response.status_code, 200)
+        data = response.json()
+        self.assertEqual(data["project_id"], "gitea-tools")
+        self.assertEqual(len(data["runnable"]), 1)
+        self.assertEqual(data["runnable"][0]["number"], 640)
+
+    def test_render_traffic_fail_closed_page(self):
+        snap = TrafficSnapshot(
+            project_id="gitea-tools",
+            repo_label="Scaled-Tech-Consulting/Gitea-Tools",
+            runnable=(),
+            leased=(),
+            blocked=(),
+            needs_controller=(),
+            terminal_complete=(),
+            next_roles=(),
+            fetch_error="Gitea credentials unavailable for gitea.prgs.cc",
+            inventory_complete=False,
+        )
+        html = render_traffic_page(snap)
+        self.assertIn("Traffic data unavailable", html)
+        self.assertIn("Fail closed", html)
+        self.assertNotIn("1. Runnable Lanes", html)
+
+
+if __name__ == "__main__":
+    unittest.main()
@@ -42,6 +42,8 @@ from webui.lease_loader import load_lease_snapshot, snapshot_to_dict as lease_sn
 from webui.lease_views import render_leases_page
 from webui.queue_loader import load_queue_snapshot, snapshot_to_dict as queue_snapshot_to_dict
 from webui.queue_views import render_queue_page
+from webui.traffic_loader import load_traffic_snapshot, snapshot_to_dict as traffic_snapshot_to_dict
+from webui.traffic_views import render_traffic_page
 from webui.worktree_scanner import load_hygiene_snapshot, snapshot_to_dict as worktree_snapshot_to_dict
 from webui.worktree_views import render_worktrees_page
 from webui.runtime_health import load_runtime_snapshot, snapshot_to_dict as runtime_snapshot_to_dict
@@ -200,6 +202,15 @@ async def api_queue(_request: Request) -> JSONResponse:
    return JSONResponse(queue_snapshot_to_dict(load_queue_snapshot()))


+async def traffic(_request: Request) -> HTMLResponse:
+    snapshot = load_traffic_snapshot()
+    return HTMLResponse(render_traffic_page(snapshot))
+
+
+async def api_traffic(_request: Request) -> JSONResponse:
+    return JSONResponse(traffic_snapshot_to_dict(load_traffic_snapshot()))
+
+
 def _load_project_registry() -> tuple[ProjectRegistry | None, RegistryError | None]:
    """Load the registry, converting validation failure into a fail-closed pair."""
    try:
@@ -736,6 +747,8 @@ def create_app(*, bind_host: str | None = None) -> Starlette:
            Route("/system-health", system_health, methods=["GET"]),
            Route("/queue", queue, methods=["GET"]),
            Route("/api/queue", api_queue, methods=["GET"]),
+            Route("/traffic", traffic, methods=["GET"]),
+            Route("/api/traffic", api_traffic, methods=["GET"]),
            Route("/projects", projects, methods=["GET"]),
            Route("/projects/{project_id}", project_detail, methods=["GET"]),
            Route("/api/projects", api_projects, methods=["GET"]),
@@ -182,10 +182,17 @@ def _extract_reviewer_leases(
            parsed = parse_reviewer_lease_comment(comment.get("body") or "")
            if not parsed:
                continue
+            subject_pr = parsed.get("pr_number") or pr_number
            leases.append(
                {
                    **parsed,
-                    "pr_number": parsed.get("pr_number") or pr_number,
+                    "pr_number": subject_pr,
+                    # The lease subject is the PR, never the linked issue: a
+                    # reviewer lease on PR #N must not be attributed to issue #N
+                    # or to the issue that PR closes (#640).
+                    "kind": "pr",
+                    "number": subject_pr,
+                    "role": "reviewer",
                    "comment_id": comment.get("id"),
                    "author": (comment.get("user") or {}).get("login"),
                    "created_at": comment.get("created_at"),
@@ -41,6 +41,7 @@ NAV_GROUPS: tuple[NavGroup, ...] = (
        NavItem("/system-health", "System health"),
    )),
    NavGroup("Traffic", (
+        NavItem("/traffic", "Traffic control"),
        NavItem("/queue", "Queue"),
        NavItem("/leases", "Leases"),
        NavItem("/actions", "Actions"),
@@ -4,7 +4,7 @@ from __future__ import annotations

 import os
 import re
-from dataclasses import dataclass
+from dataclasses import dataclass, field
 from datetime import datetime, timezone
 from typing import Any, Callable
 from urllib.parse import urlparse
@@ -31,10 +31,20 @@ class PaginationMeta:

@dataclass(frozen=True)
 class QueueItem:
+    """One queue row.
+
+    ``extra`` holds *display* strings for the queue page (values are truncated
+    or humanized for rendering). ``signals`` holds the *authoritative* typed
+    values taken straight from the Gitea payload, for consumers that classify
+    or pin state rather than render it (#640). Never derive identity or
+    concurrency decisions from ``extra``.
+    """
+
    number: int
    title: str
    badges: tuple[str, ...]
    extra: dict[str, str]
+    signals: dict[str, Any] = field(default_factory=dict)


@dataclass(frozen=True)
@@ -134,21 +144,37 @@ def _format_pr_item(pr: dict, badges: tuple[str, ...]) -> QueueItem:
        "mergeable" if mergeable is True else "conflicted" if mergeable is False else "unknown"
    )
    linked = _extract_linked_issue(pr.get("title"), pr.get("body"))
+    head_sha = str(head.get("sha") or "")
+    labels = tuple(
+        str(lb.get("name") or "") for lb in (pr.get("labels") or []) if lb.get("name")
+    )
    return QueueItem(
        number=int(pr["number"]),
        title=str(pr.get("title") or ""),
        badges=badges,
        extra={
            "branch": f"{head.get('ref', '?')} → {base.get('ref', '?')}",
-            "head_sha": str(head.get("sha") or "")[:12],
+            # Display only — truncated. Pin against signals["head_sha"] instead.
+            "head_sha": head_sha[:12],
            "mergeable": merge_label,
            "linked_issue": str(linked) if linked is not None else "",
        },
+        signals={
+            "head_sha": head_sha,
+            "head_ref": str(head.get("ref") or ""),
+            "base_ref": str(base.get("ref") or ""),
+            "mergeable": mergeable if isinstance(mergeable, bool) else None,
+            "labels": labels,
+            "linked_issue": linked,
+        },
    )


 def _format_issue_item(issue: dict, badges: tuple[str, ...]) -> QueueItem:
-    labels = ", ".join(lb.get("name", "") for lb in issue.get("labels", []))
+    label_names = tuple(
+        str(lb.get("name") or "") for lb in (issue.get("labels") or []) if lb.get("name")
+    )
+    labels = ", ".join(label_names)
    assignee = (issue.get("assignee") or {}).get("login", "")
    return QueueItem(
        number=int(issue["number"]),
@@ -159,6 +185,11 @@ def _format_issue_item(issue: dict, badges: tuple[str, ...]) -> QueueItem:
            "assignee": assignee or "unassigned",
            "state": str(issue.get("state") or ""),
        },
+        signals={
+            "labels": label_names,
+            "assignee": assignee,
+            "state": str(issue.get("state") or ""),
+        },
    )


@@ -0,0 +1,449 @@
+"""Traffic-control view loader for Phase 1 operator web console (#640).
+
+Combines queue snapshots, inventory leases, dependency graph classifications,
+and workflow dashboard rules to deliver full traffic-control visibility:
+runnable, leased (in-progress), blocked (dependency/lock), needs-controller,
+and terminal-complete candidates.
+"""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+from typing import Any, Callable, Sequence
+
+from webui.project_registry import find_project, load_registry
+from webui.queue_loader import load_queue_snapshot, QueueSnapshot
+from webui.lease_loader import load_lease_snapshot, LeaseSnapshot
+from workflow_dashboard import (
+    DashboardSnapshot,
+    QueueEntry,
+    RoleNextAction,
+    build_workflow_dashboard,
+    DASHBOARD_ROLES,
+)
+from allocator_service import WorkCandidate
+
+
+@dataclass(frozen=True)
+class TrafficItem:
+    kind: str  # "issue" or "pr"
+    number: int
+    title: str
+    traffic_state: str  # "runnable", "leased", "blocked", "needs_controller", "terminal_complete"
+    expected_role: str
+    safe_for_roles: tuple[str, ...]
+    badges: tuple[str, ...]
+    block_reason: str | None = None
+    lease_info: dict[str, Any] | None = None
+    head_sha: str | None = None
+
+    @property
+    def is_safe(self) -> bool:
+        return self.block_reason is None and bool(self.safe_for_roles)
+
+    def as_dict(self) -> dict[str, Any]:
+        return {
+            "kind": self.kind,
+            "number": self.number,
+            "title": self.title,
+            "traffic_state": self.traffic_state,
+            "expected_role": self.expected_role,
+            "safe_for_roles": list(self.safe_for_roles),
+            "badges": list(self.badges),
+            "block_reason": self.block_reason,
+            "lease_info": self.lease_info,
+            "head_sha": self.head_sha,
+            "is_safe": self.is_safe,
+        }
+
+
+@dataclass(frozen=True)
+class TrafficSnapshot:
+    project_id: str
+    repo_label: str
+    runnable: tuple[TrafficItem, ...]
+    leased: tuple[TrafficItem, ...]
+    blocked: tuple[TrafficItem, ...]
+    needs_controller: tuple[TrafficItem, ...]
+    terminal_complete: tuple[TrafficItem, ...]
+    next_roles: tuple[dict[str, Any], ...]
+    fetch_error: str | None = None
+    inventory_complete: bool = True
+
+    def as_dict(self) -> dict[str, Any]:
+        return {
+            "project_id": self.project_id,
+            "repo_label": self.repo_label,
+            "runnable": [i.as_dict() for i in self.runnable],
+            "leased": [i.as_dict() for i in self.leased],
+            "blocked": [i.as_dict() for i in self.blocked],
+            "needs_controller": [i.as_dict() for i in self.needs_controller],
+            "terminal_complete": [i.as_dict() for i in self.terminal_complete],
+            "next_roles": list(self.next_roles),
+            "fetch_error": self.fetch_error,
+            "inventory_complete": self.inventory_complete,
+        }
+
+
+def _classify_traffic_item(
+    entry: QueueEntry,
+    *,
+    lease_info: dict[str, Any] | None = None,
+) -> TrafficItem:
+    """Classify a QueueEntry into a TrafficItem with explicit traffic state."""
+    badges = list(entry.badges)
+    block_reason = entry.block_reason
+    expected_role = entry.expected_role
+
+    entry_is_safe = entry.block_reason is None and bool(entry.safe_for_roles)
+    # Lease state is checked first: an item that is both leased and blocked is
+    # reported as leased. That is safe by construction — a leased item is never
+    # placed in the runnable lane — and it keeps the operator's attention on the
+    # session that currently owns the work. The blocker text still renders.
+    if lease_info is not None or "in-progress" in badges or "claimed" in badges:
+        state = "leased"
+    elif expected_role == "reconciler" or "terminal-lock" in badges:
+        state = "terminal_complete"
+    elif expected_role == "controller" or "contaminated" in badges or "needs-controller" in badges:
+        state = "needs_controller"
+    elif (
+        block_reason is not None
+        or "blocked" in badges
+        or "dependency-unmet" in badges
+        or "blocked-by-terminal" in badges
+        or "status:blocked" in badges
+    ):
+        state = "blocked"
+    elif entry_is_safe:
+        state = "runnable"
+    else:
+        state = "needs_controller"
+
+    return TrafficItem(
+        kind=entry.kind,
+        number=entry.number,
+        title=entry.title,
+        traffic_state=state,
+        expected_role=expected_role,
+        safe_for_roles=entry.safe_for_roles,
+        badges=tuple(badges),
+        block_reason=block_reason,
+        lease_info=lease_info,
+        head_sha=entry.head_sha,
+    )
+
+
+# Claim statuses from ``issue_claim_heartbeat.build_claim_inventory`` that mean
+# a live worker currently holds the issue. Everything else (``stale``,
+# ``phantom``, ``reclaimable``, ``not_claimed``) is reported through the
+# dashboard's stale-lease channel and is never rendered as an active lease.
+_ACTIVE_CLAIM_STATUSES = frozenset({"active", "awaiting_review"})
+
+# Statuses that positively mean "not an active lease" for any lease record.
+_INACTIVE_LEASE_STATUSES = frozenset(
+    {"expired", "stale", "released", "moot", "reclaimable", "phantom", "not_claimed"}
+)
+
+
+def _candidates_from_queue_snapshot(q_snap: QueueSnapshot) -> list[WorkCandidate]:
+    """Build allocator candidates from the queue loader's authoritative signals.
+
+    Display badges (``blocked``/``claimed``/``duplicate``/``stale``/
+    ``in-review``/``open``) are rendering hints, not routing state, so nothing
+    here branches on them. Every routing field comes from
+    ``QueueItem.signals`` — the raw Gitea payload values.
+
+    The queue loader reads ``/pulls`` and ``/issues`` only; it never fetches
+    review verdicts. ``request_changes_current_head`` / ``approval_on_current_head``
+    are therefore left at their fail-safe ``False`` rather than being guessed
+    from badges: an unproven approval must never route a PR to the merger.
+    """
+    candidates: list[WorkCandidate] = []
+
+    for pr in q_snap.prs:
+        signals = pr.signals or {}
+        head_sha = str(signals.get("head_sha") or "").strip()
+        mergeable = signals.get("mergeable")
+        labels = tuple(str(x) for x in (signals.get("labels") or ()))
+        candidates.append(
+            WorkCandidate(
+                kind="pr",
+                number=pr.number,
+                state="open",
+                labels=labels,
+                title=pr.title,
+                # Full 40-char SHA from head.sha — never the 12-char display value.
+                head_sha=head_sha or None,
+                priority=5,
+                mergeable=mergeable is True,
+                blocked=mergeable is False or "status:blocked" in labels,
+            )
+        )
+
+    for issue in q_snap.issues:
+        signals = issue.signals or {}
+        labels = tuple(str(x) for x in (signals.get("labels") or ()))
+        lowered = {label.lower() for label in labels}
+        candidates.append(
+            WorkCandidate(
+                kind="issue",
+                number=issue.number,
+                state="open",
+                labels=labels,
+                title=issue.title,
+                priority=20 if "status:ready" in lowered else 10,
+                blocked="status:blocked" in lowered,
+                # A live claim by another session is not this session's work.
+                already_claimed_elsewhere="status:in-progress" in lowered,
+            )
+        )
+
+    return candidates
+
+
+def _claim_lease_records(inventory: dict[str, Any] | None) -> list[dict[str, Any]]:
+    """Normalize ``build_claim_inventory`` entries into lease records.
+
+    The inventory contract is ``{"entries", "counts", "heartbeat_lease_minutes",
+    "reclaim_after_minutes", "in_progress_total"}``. Each entry is keyed by
+    ``issue_number``; the subject kind is therefore always ``issue``.
+    """
+    entries = (inventory or {}).get("entries") or ()
+    records: list[dict[str, Any]] = []
+    for entry in entries:
+        if not isinstance(entry, dict):
+            continue
+        number = entry.get("issue_number")
+        if number is None:
+            continue
+        try:
+            number_int = int(number)
+        except (TypeError, ValueError):
+            continue
+        heartbeat = entry.get("latest_heartbeat") or {}
+        record = dict(entry)
+        record.update(
+            {
+                "kind": "issue",
+                "number": number_int,
+                "role": "author",
+                "lease_source": "issue-claim-heartbeat",
+            }
+        )
+        if isinstance(heartbeat, dict):
+            if heartbeat.get("session_id") and not record.get("session_id"):
+                record["session_id"] = heartbeat.get("session_id")
+            if heartbeat.get("author") and not record.get("author"):
+                record["author"] = heartbeat.get("author")
+        records.append(record)
+    return records
+
+
+def _lease_subject(lease: dict[str, Any]) -> tuple[str, int] | None:
+    """Return the ``(kind, number)`` a lease record actually covers.
+
+    Fails closed: a record that does not identify exactly one subject is
+    dropped rather than attributed to a guessed work item (#640 — never invent
+    a lease, and never attach a PR lease to a same-numbered issue).
+    """
+    kind = str(lease.get("kind") or lease.get("work_kind") or "").strip().lower()
+    pr_number = lease.get("pr_number")
+    issue_number = lease.get("issue_number")
+
+    if kind not in ("pr", "issue"):
+        if pr_number is not None and issue_number is None:
+            kind = "pr"
+        elif issue_number is not None and pr_number is None:
+            kind = "issue"
+        else:
+            return None
+
+    number = lease.get("number")
+    if number is None:
+        number = lease.get("work_number")
+    if number is None:
+        number = pr_number if kind == "pr" else issue_number
+    if number is None:
+        return None
+    try:
+        return kind, int(number)
+    except (TypeError, ValueError):
+        return None
+
+
+def _is_active_lease(lease: dict[str, Any]) -> bool:
+    """True when the record proves a worker currently holds the item."""
+    if lease.get("stale") or lease.get("expired"):
+        return False
+    status = str(lease.get("status") or lease.get("lease_status") or "").strip().lower()
+    if status in _INACTIVE_LEASE_STATUSES:
+        return False
+    if lease.get("lease_source") == "issue-claim-heartbeat":
+        return status in _ACTIVE_CLAIM_STATUSES
+    return True
+
+
+def load_traffic_snapshot(
+    *,
+    candidates: Sequence[WorkCandidate] | None = None,
+    leases: Sequence[dict[str, Any]] | None = None,
+    terminal_pr: int | None = None,
+    fetch_queue_snapshot: Callable[[], QueueSnapshot] | None = None,
+    fetch_lease_snapshot: Callable[[], LeaseSnapshot] | None = None,
+    project_id: str = "gitea-tools",
+) -> TrafficSnapshot:
+    """Load and compute the traffic-control snapshot."""
+    try:
+        reg = load_registry()
+        proj = find_project(reg, project_id)
+        repo_label = proj.remote_repo if proj else "Scaled-Tech-Consulting/Gitea-Tools"
+    except Exception:
+        repo_label = "Scaled-Tech-Consulting/Gitea-Tools"
+
+    # Injected candidates path (pure unit testing)
+    if candidates is not None:
+        dashboard = build_workflow_dashboard(
+            candidates=candidates,
+            leases=leases,
+            terminal_pr=terminal_pr,
+            inventory_complete=True,
+        )
+        return _build_traffic_snapshot_from_dashboard(
+            project_id=project_id,
+            repo_label=repo_label,
+            dashboard=dashboard,
+            leases=leases or (),
+        )
+
+    # Live snapshot loading
+    q_loader = fetch_queue_snapshot or load_queue_snapshot
+    l_loader = fetch_lease_snapshot or load_lease_snapshot
+
+    try:
+        q_snap = q_loader()
+        l_snap = l_loader()
+    except Exception as exc:  # noqa: BLE001
+        return TrafficSnapshot(
+            project_id=project_id,
+            repo_label=repo_label,
+            runnable=(),
+            leased=(),
+            blocked=(),
+            needs_controller=(),
+            terminal_complete=(),
+            next_roles=(),
+            fetch_error=f"Failed to load traffic state: {exc}",
+            inventory_complete=False,
+        )
+
+    if q_snap.fetch_error or l_snap.fetch_error:
+        err = q_snap.fetch_error or l_snap.fetch_error
+        return TrafficSnapshot(
+            project_id=project_id,
+            repo_label=repo_label,
+            runnable=(),
+            leased=(),
+            blocked=(),
+            needs_controller=(),
+            terminal_complete=(),
+            next_roles=(),
+            fetch_error=err,
+            inventory_complete=False,
+        )
+
+    candidate_list = _candidates_from_queue_snapshot(q_snap)
+
+    raw_leases: list[dict[str, Any]] = _claim_lease_records(l_snap.claim_inventory)
+    for r_lease in l_snap.reviewer_leases or ():
+        if not isinstance(r_lease, dict):
+            continue
+        # Always pin reviewer leases to the PR subject, even if a linked
+        # issue_number is present on the marker (#640 B2).
+        normalized = dict(r_lease)
+        subject = normalized.get("pr_number") or normalized.get("number")
+        if subject is None:
+            continue
+        try:
+            pr_num = int(subject)
+        except (TypeError, ValueError):
+            continue
+        normalized["kind"] = "pr"
+        normalized["number"] = pr_num
+        normalized["pr_number"] = pr_num
+        normalized.setdefault("role", "reviewer")
+        raw_leases.append(normalized)
+
+    dashboard = build_workflow_dashboard(
+        candidates=candidate_list,
+        leases=raw_leases,
+        inventory_complete=q_snap.pr_pagination.inventory_complete if q_snap.pr_pagination else True,
+    )
+
+    return _build_traffic_snapshot_from_dashboard(
+        project_id=project_id,
+        repo_label=repo_label,
+        dashboard=dashboard,
+        leases=raw_leases,
+    )
+
+
+def _build_traffic_snapshot_from_dashboard(
+    *,
+    project_id: str,
+    repo_label: str,
+    dashboard: DashboardSnapshot,
+    leases: Sequence[dict[str, Any]],
+) -> TrafficSnapshot:
+    """Classify dashboard entries into the 5 traffic state buckets."""
+    all_entries = dashboard.open_prs + dashboard.open_issues
+
+    # Map each active lease onto the exact work item it covers. Records whose
+    # subject cannot be determined, and claims that are stale/phantom/
+    # reclaimable, are deliberately dropped instead of guessed.
+    lease_map: dict[tuple[str, int], dict[str, Any]] = {}
+    for lease in leases:
+        if not isinstance(lease, dict) or not _is_active_lease(lease):
+            continue
+        subject = _lease_subject(lease)
+        if subject is not None:
+            lease_map[subject] = lease
+
+    runnable: list[TrafficItem] = []
+    leased: list[TrafficItem] = []
+    blocked: list[TrafficItem] = []
+    needs_controller: list[TrafficItem] = []
+    terminal_complete: list[TrafficItem] = []
+
+    for entry in all_entries:
+        l_info = lease_map.get((entry.kind, entry.number))
+        item = _classify_traffic_item(entry, lease_info=l_info)
+
+        if item.traffic_state == "leased":
+            leased.append(item)
+        elif item.traffic_state == "terminal_complete":
+            terminal_complete.append(item)
+        elif item.traffic_state == "blocked":
+            blocked.append(item)
+        elif item.traffic_state == "needs_controller":
+            needs_controller.append(item)
+        else:
+            runnable.append(item)
+
+    next_roles = [dashboard.next_safe_by_role[r].as_dict() for r in DASHBOARD_ROLES if r in dashboard.next_safe_by_role]
+
+    return TrafficSnapshot(
+        project_id=project_id,
+        repo_label=repo_label,
+        runnable=tuple(runnable),
+        leased=tuple(leased),
+        blocked=tuple(blocked),
+        needs_controller=tuple(needs_controller),
+        terminal_complete=tuple(terminal_complete),
+        next_roles=tuple(next_roles),
+        fetch_error=None,
+        inventory_complete=dashboard.inventory_complete,
+    )
+
+
+def snapshot_to_dict(snapshot: TrafficSnapshot) -> dict[str, Any]:
+    return snapshot.as_dict()
@@ -0,0 +1,170 @@
+"""HTML rendering for Phase 1 Traffic-Control View (#640)."""
+
+from __future__ import annotations
+
+from html import escape
+from typing import Sequence
+
+from webui.layout import render_page
+from webui.traffic_loader import TrafficItem, TrafficSnapshot
+
+
+def _render_badges(badges: Sequence[str]) -> str:
+    if not badges:
+        return ""
+    out = []
+    for b in badges:
+        cls = "badge"
+        b_lower = b.lower()
+        if "blocked" in b_lower or "unmet" in b_lower:
+            cls += " badge-blocked"
+        elif "claimed" in b_lower or "in-progress" in b_lower or "leased" in b_lower:
+            cls += " badge-claimed"
+        elif "review" in b_lower or "ready" in b_lower:
+            cls += " badge-in-review"
+        elif "duplicate" in b_lower:
+            cls += " badge-duplicate"
+        elif "stale" in b_lower:
+            cls += " badge-stale"
+        out.append(f'<span class="{cls}">{escape(b)}</span>')
+    return f'<div class="badges">{"".join(out)}</div>'
+
+
+def _render_traffic_item_row(item: TrafficItem) -> str:
+    kind_label = escape(item.kind.upper())
+    num_str = f"#{item.number}"
+    title_str = escape(item.title)
+    role_str = escape(item.expected_role)
+    badges_html = _render_badges(item.badges)
+    
+    reason_html = ""
+    if item.block_reason:
+        reason_html = f'<div class="muted" style="font-size:0.82rem; margin-top:0.2rem;"><strong>Blocker:</strong> {escape(item.block_reason)}</div>'
+
+    lease_html = ""
+    if item.lease_info:
+        owner = escape(str(item.lease_info.get("session_id") or item.lease_info.get("reviewer_identity") or "active worker"))
+        lease_html = f'<div class="muted" style="font-size:0.82rem; margin-top:0.2rem;"><strong>Lease:</strong> {owner}</div>'
+
+    return f"""<tr>
+  <td><code>{kind_label} {num_str}</code></td>
+  <td>
+    <div><strong>{title_str}</strong> {badges_html}</div>
+    {reason_html}
+    {lease_html}
+  </td>
+  <td><code>{role_str}</code></td>
+</tr>"""
+
+
+def _render_traffic_table(items: Sequence[TrafficItem], empty_message: str) -> str:
+    if not items:
+        return f'<p class="muted">{escape(empty_message)}</p>'
+    
+    rows = "".join(_render_traffic_item_row(item) for item in items)
+    return f"""<table class="registry">
+  <thead>
+    <tr>
+      <th style="width: 15%;">Item</th>
+      <th style="width: 65%;">Title & Details</th>
+      <th style="width: 20%;">Next Role</th>
+    </tr>
+  </thead>
+  <tbody>
+    {rows}
+  </tbody>
+</table>"""
+
+
+def _render_next_roles(next_roles: Sequence[dict]) -> str:
+    if not next_roles:
+        return ""
+    
+    cards = []
+    for r in next_roles:
+        role = escape(r.get("role", "unknown"))
+        status = r.get("status", "idle")
+        prompt = escape(r.get("prompt", ""))
+        
+        status_cls = "badge-health-ok" if status == "safe" else ("badge-blocked" if "blocked" in status else "badge-health-skipped")
+        cards.append(f"""<div class="health-card" style="margin-bottom:0.75rem;">
+  <div style="display:flex; justify-content:space-between; align-items:center;">
+    <h3>Role: <code>{role}</code></h3>
+    <span class="badge {status_cls}">status: {escape(status)}</span>
+  </div>
+  <p class="meta" style="margin:0.35rem 0 0;">{prompt}</p>
+</div>""")
+    
+    return f"""<div style="margin: 1.5rem 0;">
+  <h3>Next Safe Role Actions</h3>
+  {"".join(cards)}
+</div>"""
+
+
+def render_traffic_page(snapshot: TrafficSnapshot) -> str:
+    """Render the full HTML view for workflow traffic control."""
+    if snapshot.fetch_error:
+        body = f"""<h2>Workflow Traffic Control</h2>
+<p class="meta">Repository: <code>{escape(snapshot.repo_label)}</code></p>
+<div class="health-card health-stale">
+  <h3>Traffic data unavailable</h3>
+  <p class="health-headline">{escape(snapshot.fetch_error)}</p>
+  <p class="muted">Fail closed: traffic state cannot be established cleanly. Check credentials or remote connectivity.</p>
+</div>"""
+        return render_page(title="Traffic Control", body_html=body)
+
+    runnable_count = len(snapshot.runnable)
+    leased_count = len(snapshot.leased)
+    blocked_count = len(snapshot.blocked)
+    controller_count = len(snapshot.needs_controller)
+    terminal_count = len(snapshot.terminal_complete)
+
+    summary_bar = f"""<div class="health-card" style="display:flex; flex-wrap:wrap; gap:1rem; align-items:center;">
+  <div><strong>Runnable:</strong> <span class="badge badge-health-ok">{runnable_count}</span></div>
+  <div><strong>Leased:</strong> <span class="badge badge-claimed">{leased_count}</span></div>
+  <div><strong>Blocked:</strong> <span class="badge badge-blocked">{blocked_count}</span></div>
+  <div><strong>Needs Controller:</strong> <span class="badge badge-duplicate">{controller_count}</span></div>
+  <div><strong>Terminal Complete:</strong> <span class="badge badge-stale">{terminal_count}</span></div>
+</div>"""
+
+    next_roles_html = _render_next_roles(snapshot.next_roles)
+
+    sections_html = f"""
+<div class="prompt-card">
+  <h3>1. Runnable Lanes (Ready for Allocation)</h3>
+  <p class="muted">Safe work items with no unmet dependencies or active leases. Safe for allocation.</p>
+  {_render_traffic_table(snapshot.runnable, "No runnable items ready for allocation.")}
+</div>
+
+<div class="prompt-card">
+  <h3>2. In-Progress Work (Active Leases)</h3>
+  <p class="muted">Work items currently leased and actively being worked by an assigned role session.</p>
+  {_render_traffic_table(snapshot.leased, "No active leases in flight.")}
+</div>
+
+<div class="prompt-card">
+  <h3>3. Blocked Items (Dependencies / Locks)</h3>
+  <p class="muted">Items blocked by unmet dependency issues, status:blocked, or active terminal review locks. Never presented as safe.</p>
+  {_render_traffic_table(snapshot.blocked, "No blocked items.")}
+</div>
+
+<div class="prompt-card">
+  <h3>4. Needs Controller Intervention</h3>
+  <p class="muted">Items requiring controller routing, diagnosis, or cross-role assignment.</p>
+  {_render_traffic_table(snapshot.needs_controller, "No items requiring controller intervention.")}
+</div>
+
+<div class="prompt-card">
+  <h3>5. Terminal / Complete Candidates</h3>
+  <p class="muted">Items ready for terminal reconciliation or post-merge worktree cleanup.</p>
+  {_render_traffic_table(snapshot.terminal_complete, "No terminal complete candidates.")}
+</div>
+"""
+
+    body = f"""<h2>Workflow Traffic Control</h2>
+<p class="meta">Repository: <code>{escape(snapshot.repo_label)}</code></p>
+{summary_bar}
+{next_roles_html}
+{sections_html}"""
+
+    return render_page(title="Traffic Control", body_html=body)