Simplifies the PlaylistBase id field to a non-optional int and updates database logic to use session.refresh for id assignment. Adds Alembic migration to include created_at and updated_at columns in room_playlists for timestamp tracking.
Introduces a new /beatmaps/ensure API endpoint to verify and cache beatmap metadata and raw files. Updates Playlist model to use auto-incrementing primary key and improves playlist DB insertion logic. Minor formatting and import changes in room and lio modules.
Introduces created_at and updated_at fields to the Playlist model for tracking creation and modification times. Refactors room user removal logic to handle owner transfer and participant count updates more robustly. Updates room query logic for more accurate filtering by category and status. Adds migration stubs for updated_at column in room playlists.
