Three unbounded or stale surfaces, each small on its own: - lyrics_index rows were never pruned on track removal, so the FTS index grew forever. Delete the entry where the library search FTS entry is already deleted, on the orphan and RemoveFromLibrary paths. - search_clicks had no ceiling; age out ranking rows after a retention window via a daily janitor job. - queue.source_* kept a "Playing from X" label after its playlist was deleted. Drop the source when the queue's own playlist goes, wired through a playlist-service hook like Library.SetRemovalHooks. Closes #249