- Update _update_series_in_db to sync missing episodes bidirectionally
- Add delete_by_series_and_episode method to EpisodeService
- Remove downloaded episodes from DB after successful download
- Clear anime service cache when episodes are removed
- Fix tests to use 'message' instead of 'detail' in API responses
- Mock DB operations in rescan tests
- Updated AnimeSeries model docstring to clarify key is primary identifier
- Updated folder field to indicate metadata-only usage
- Updated AnimeSeriesService docstring and get_by_key method
- Updated infrastructure.md with database identifier documentation
- All 996 tests passing