- Updated `README.md` to include instructions for setting up the TMDB API key and new admin endpoints for managing country metadata.
- Implemented `/admin/missing-countries` endpoint to list media items without country metadata, with filtering options for source and media type.
- Added `/admin/assign-country` endpoint to manually assign a country code to a media item.
- Enhanced country extraction logic in `sync.py` to utilize TMDB and MusicBrainz APIs for automatic country retrieval based on available metadata.
- Updated configuration in `config.py` to include optional TMDB API key setting.
- Improved error handling and logging for country extraction failures.
- Ensured that country data is stored and utilized during media item synchronization across Radarr, Sonarr, and Lidarr.
- Removed direct pool checks and replaced them with a centralized database initialization method in `init_db`.
- Updated API endpoints in `admin.py`, `collection.py`, `pins.py`, and `watched.py` to ensure the database connection pool is initialized before usage.
- Enhanced error handling to raise HTTP exceptions if the database is unavailable.
- Improved the `init_db` function in `database.py` to prevent multiple simultaneous initializations using an asyncio lock.
