feat(FN-5528): add soft-delete exclusion to stale blocked-by recovery scrip

Adds `deletedAt` sweep guards to the engine's self-healing and merger to prevent recovery operations from processing soft-deleted tasks, filters deleted tasks in the `recover-stale-blocked-by` script, includes a new regression test for the deadlock-scan exclusion pattern, and updates the soft-delete

Fusion-Task-Id: FN-5528

Fusion-Task-Lineage: 5c9e45ca-49a8-47a0-a23d-6fe8e15e7e00

Co-authored-by: Fusion (runfusion.ai) <noreply@runfusion.ai>
Fusion-Task-Id: FN-5528

docs/soft-delete-verification-matrix.md

@@ -20,7 +20,7 @@
 | 8. Soft-delete a `done` task with archived/visible agent logs and saved task documents | Live `done`; has task docs + agent logs | Delete succeeds; live task readers omit afterward; forensic reads still allowed internally | Not runnable after any engine tick or restart | N/A | N/A | SSE removes card; refresh does not show it in board/ListView/TodoView | `agentLogEntries` must clear atomically; **pending FN-5143** | `/api/documents` and per-task docs must disappear while DB rows remain; **pending FN-5140** | FN-5140 / FN-5143 |
 | 9. Soft-delete an archived task | Task already archived / moved out of live `tasks` table | Current contract is not pinned; matrix gate requires deterministic error-or-no-op behavior. Follow-up filed as **FN-5196**. | Must never affect active queues either way | N/A | N/A | No dashboard resurrection; exact UX blocked by FN-5196 | N/A | N/A | FN-5196 |
 | 10. Soft-delete a task that is checked out by an agent (`checkedOutBy` set) | Live task with lease / checkout metadata | Delete succeeds; linked agent task references clear with delete | Soft-deleted checked-out task must not be auto-claimed or executed after refresh/tick; extra deterministic coverage filed as **FN-5195** | If merge-owned, FN-5142 owns active merge abort details | If triage-owned, FN-5142 owns active triage abort details | SSE removes card; refresh must not show stale checked-out task | Preserved until FN-5143 | Hidden from live readers once FN-5140 lands | FN-5137 / FN-5195 |
-| 11. Retry-exhausted `in-review` blocker is soft-deleted (`mergeRetries >= 3`) | Row remains in `tasks` with `deletedAt` set; downstream live tasks may still reference blocker in `dependencies`/`blockedBy` | Default task readers still hide it; opt-in surfaces expose it (`GET /api/tasks/exhausted-in-review?includeDeleted=true`, `GET /api/tasks/:id?includeDeleted=true`, `fn_task_show` fallback, `fn_task_list includeDeleted`) | No scheduler/executor resurrection; visibility only | No merge-state mutation; blocker remains terminal unless explicit operator action | N/A | ReliabilityView panel explicitly lists hidden exhausted blockers + blocked dependents; main board stays unchanged | Existing logs preserved | Documents readable via opt-in task-detail fetch; no automatic restore | FN-5513 |
+| 11. Retry-exhausted `in-review` blocker is soft-deleted (`mergeRetries >= 3`) | Row remains in `tasks` with `deletedAt` set; downstream live tasks may still reference blocker in `dependencies`/`blockedBy` | Default task readers still hide it; opt-in surfaces expose it (`GET /api/tasks/exhausted-in-review?includeDeleted=true`, `GET /api/tasks/:id?includeDeleted=true`, `fn_task_show` fallback, `fn_task_list includeDeleted`) | Deadlock/stuck-merge/in-review-stall scans must exclude soft-deleted rows via `listTasks` (`ACTIVE_TASKS_WHERE`), plus per-sweep `task.deletedAt` guards as belt-and-suspenders | No merge-state mutation; blocker remains terminal unless explicit operator action | N/A | ReliabilityView panel explicitly lists hidden exhausted blockers + blocked dependents; main board stays unchanged | Existing logs preserved | Documents readable via opt-in task-detail fetch; no automatic restore | FN-5513 / FN-5528 |
 
 ## ID reservation invariant
 
@@ -38,6 +38,7 @@
 | 4,5 | In-flight executor / workflow-step / reviewer abort on `task:deleted` | Entry-guard coverage only; no active-session abort assertion | Missing deterministic abort + dispose assertions | `packages/engine/src/__tests__/executor-soft-delete-abort.test.ts` and `packages/engine/src/__tests__/reliability-interactions/soft-delete-in-flight-abort.test.ts` | FN-5142 |
 | 6,7 | In-flight merge abort / merge queue filtering | No deterministic merge-abort assertion in current corpus | Missing active merge abort + queued merge filtering coverage | `packages/engine/src/__tests__/project-engine-soft-delete-merge-abort.test.ts` | FN-5142 |
 | 1,10 | Triage abort on `task:deleted` | No deterministic triage abort assertion in current corpus | Missing active triage session + subagent abort coverage | `packages/engine/src/__tests__/triage-soft-delete-abort.test.ts` | FN-5142 |
+| 11 | Deadlock/stuck-merge/in-review-stall scan exclusion for soft-deleted exhausted blockers | Added in this task | GREEN — defensive sweep guards + script `WHERE deletedAt IS NULL` backstop | `packages/engine/src/__tests__/reliability-interactions/soft-delete-deadlock-scan-exclusion.test.ts`, `scripts/__tests__/recover-stale-blocked-by.test.mjs` | FN-5528 |
 | 8 | `agentLogEntries` cleared on soft-delete | No dedicated coverage today | Missing atomic clear + post-delete empty-reader assertion | `packages/core/src/__tests__/soft-delete-agent-logs.test.ts` | FN-5143 |
 | 8 | `/api/documents` and per-task docs exclude soft-deleted parents | No dedicated soft-delete document visibility assertion today | Missing store + route coverage | `packages/core/src/__tests__/task-documents.test.ts` and `packages/dashboard/src/__tests__/routes-tasks.test.ts` | FN-5140 |
 | 3 | Lineage-unlink 409 flow through API + UI | Store lineage guards are covered; route/UI flow is not | Missing 409 payload + confirm-retry UX coverage | `packages/dashboard/src/__tests__/routes-tasks-ops.test.ts`, `packages/dashboard/app/utils/__tests__/taskDelete.test.ts`, `packages/dashboard/app/components/__tests__/TaskCard.test.tsx`, `packages/dashboard/app/components/__tests__/TaskDetailModal.responsive-and-dependencies.test.tsx`, `packages/dashboard/app/components/__tests__/ListView.test.tsx` | FN-5139 |