fix: durable author worktree resolution without control fallback (Closes #618)

Author mutation tools now resolve workspace via explicit worktree_path,
env bindings, or the active author issue lock — never silent fallback to
the control checkout/master. Missing configured bindings fail closed with
operator recovery; create_issue and create_issue_comment agree.

Recovered onto 0568f44 from preserved candidate cbf56ccd (AUTHOR_RECOVERY).
LLM_LOCK_ID=author-618-recovery-508eb3162d01-1784569919

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

thread_state_ledger_examples.py

@@ -523,6 +523,49 @@ Who/what acts next:
 - Required action: implement #507 two-comment validator
 - Do not do: recreate duplicate CTH issue
 - Resume from: issue #507 body
+""",
+    )
+)
+
+EXAMPLES.append(
+    _example(
+        "bound_worktree_missing_blocker",
+        """
+[CONTROLLER HANDOFF] Issue #618 — author mutation blocked
+
+Server-side mutation ledger:
+- none — no server-side state changed
+
+Blockers:
+- environment/tooling blocker: bound worktree missing; operator must recreate or repoint the worktree and reconnect
+""",
+        """
+[THREAD STATE LEDGER] Issue #618 — author worktree binding unhealthy
+
+What is true now:
+- Issue state: open
+- Server-side decision state: no server-side state changed
+- Local verdict/state: author mutation tools fail closed consistently
+- Latest known validation: runtime context reports workspace_healthy=false
+- Role/profile: prgs-author
+- Configured worktree path: branches/mcp-author-clean-ns (via GITEA_AUTHOR_WORKTREE)
+- path_exists: false
+- in_git_worktree_list: false
+- inspected_git_root: null
+
+What changed:
+- nothing server-side; local env still points at a deleted role-bound worktree
+
+What is blocked:
+- Blocker classification: environment/tooling blocker
+- Blocker detail: bound worktree missing; operator must recreate or repoint the worktree and reconnect
+- create_issue and create_issue_comment (and other author mutations) agree: fail closed before API mutation
+
+Who/what acts next:
+- Next actor: operator
+- Required action: recreate the worktree under branches/ (scripts/worktree-start or git worktree add), set GITEA_AUTHOR_WORKTREE / GITEA_ACTIVE_WORKTREE to that path (or pass worktree_path), keep control checkout clean on master, reconnect the author MCP session, then re-run the mutation
+- Do not do: retry mutations hoping create_issue_comment will still work while create_issue blocks; do not fall back to the control checkout or master
+- Resume from: healthy author worktree binding + gitea_whoami + gitea_resolve_task_capability
 """,
     )
 )