feat: add worktree cleanup audit integrity (Closes #404)

Reconcile before/after branches/ snapshots so preserved worktrees cannot
disappear without removal logs or explained state transitions.

- worktree_cleanup_audit.py: snapshot capture, disposition reconciliation
- gitea_capture_branches_worktree_snapshot, gitea_assess_worktree_cleanup_integrity
- Final-report rule author.worktree_cleanup_audit_proof
- worktree-cleanup.md bulk audit section
- tests/test_worktree_cleanup_audit.py (11 cases)

gitea_mcp_server.py

@@ -504,6 +504,7 @@ import already_landed_reconcile  # noqa: E402
 import author_mutation_worktree  # noqa: E402
 import issue_claim_heartbeat  # noqa: E402
 import merged_cleanup_reconcile  # noqa: E402
+import worktree_cleanup_audit  # noqa: E402
 import reconciler_profile  # noqa: E402
 import reconciliation_workflow  # noqa: E402
 import review_merge_state_machine  # noqa: E402
@@ -3509,6 +3510,59 @@ def _remote_branch_exists(h: str, o: str, r: str, auth: str, branch: str) -> boo
         raise
 
 
+@mcp.tool()
+def gitea_capture_branches_worktree_snapshot(
+    open_pr_branches: list[str] | None = None,
+    active_lock_branch: str | None = None,
+    leased_paths: list[str] | None = None,
+    worktree_path: str | None = None,
+) -> dict:
+    """Read-only: capture ``branches/`` and worktree audit snapshot (#404)."""
+    read_block = _profile_operation_gate("gitea.read")
+    if read_block:
+        return {
+            "success": False,
+            "reasons": read_block,
+            "permission_report": _permission_block_report("gitea.read"),
+        }
+    root = PROJECT_ROOT
+    if worktree_path:
+        root = os.path.realpath(os.path.abspath(worktree_path))
+        git_root = _get_git_root(root)
+        if git_root:
+            root = git_root
+    snapshot = worktree_cleanup_audit.capture_branches_worktree_snapshot(
+        root,
+        open_pr_branches=open_pr_branches,
+        active_lock_branch=active_lock_branch,
+        leased_paths=leased_paths,
+    )
+    return {"success": True, "snapshot": snapshot}
+
+
+@mcp.tool()
+def gitea_assess_worktree_cleanup_integrity(
+    before_snapshot: dict,
+    after_snapshot: dict,
+    removals: list[dict] | None = None,
+    explained_missing: dict[str, str] | None = None,
+) -> dict:
+    """Read-only: reconcile cleanup before/after snapshots (#404)."""
+    read_block = _profile_operation_gate("gitea.read")
+    if read_block:
+        return {
+            "integrity_passed": False,
+            "reasons": read_block,
+            "permission_report": _permission_block_report("gitea.read"),
+        }
+    return worktree_cleanup_audit.assess_worktree_cleanup_integrity(
+        before=before_snapshot,
+        after=after_snapshot,
+        removals=removals,
+        explained_missing=explained_missing,
+    )
+
+
 @mcp.tool()
 def gitea_reconcile_merged_cleanups(
     dry_run: bool = True,