Fixes a race condition (TOCTOU) in ActorLoader.list_actors() where the namespace
filter was applied outside the threading lock, creating a window for concurrent
dictionary modifications. Moving the filter inside the with self._lock: block
ensures atomic reads and filtering.
- Move namespace filtering inside the RLock in list_actors()
- Add concurrency BDD test (threading.Barrier) for list_actors + clear race condition
- Update CHANGELOG.md with fix entry (closes#8588)
- Update CONTRIBUTORS.md with contribution details
ISSUES CLOSED: #8588
Renamed 'listing actors with namespace' step in actor_loading_steps.py
to 'listing loaded actors with namespace' to avoid collision with
actor_registry_persistence_steps.py from master. Updated
actor_loading.feature to use renamed step.
HAL9000
brent.edwards
aditya
