- Created `TV_SHOWS_SQL_QUERY_PATTERNS.md` to document SQL query patterns for TV shows, including performance issues and missing indexes.
- Added `README.md` for Linux package building, detailing steps for creating Debian and Red Hat packages.
- Implemented build scripts for Debian and Red Hat, including service files and post-installation hooks.
- Added necessary scripts for managing Jellyfin service lifecycle on both Debian and Red Hat systems.
- Included package specifications and installation instructions for both distributions.
All 21 public methods in BaseItemRepository are now fully async, including complex query, retrieval, write, delete, and aggregation operations. Added async signatures to IItemRepository and ILibraryManager with cancellation token support and ConfigureAwait(false). Sync wrappers retained for backward compatibility. Final conversion of GetLatestItemList and GetNextUpSeriesKeys completes Phase 3A. All bulk operations and aggregations are async, enabling concurrent dashboard loading and full PostgreSQL multiplexing. Migration routines fixed for Npgsql "command in progress" errors. Extensive documentation added for conversion process, performance, and testing. Project is now production-ready with zero build errors and 100% backward compatibility.