Release v1.33.0

feat(swarm): add timeout handling, session locking, and commit tracking

- Implement proper timeout with Child::try_wait() polling loop
- Use sh -c for shell command execution (handles pipes, quotes)
- Add session locking via fs2 to prevent concurrent swarm runs
- Track start_commit in WaveState for accurate file change detection
- Update collect_changed_files to use commit range
- Remove unused all_tasks_flat parameter from compute_waves_from_tasks
- Add comprehensive unit tests for timeout, locking, and git commit

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>