- Add completion handoff limbo recovery state to task storage and audit events for bounded self-healing retries
- Requeue eligible in-review tasks stuck after "Task marked done by agent" with grace-period, active-task, and merge-blocker safeguards
- Isolate executor run mutation context per task to prevent cross-task runId attribution leaks in scope-leak and completion logs
- Add reliability and executor regression tests covering limbo recovery, run-context isolation, and updated persistence behavior
Fusion-Task-Id: FN-4999
