v2.2.1

Fix: series episodes/torrents now persist.

CreateEpisode upserts with ON CONFLICT(series_id, season_number, episode_number), which SQLite requires a matching UNIQUE index for. The Episode model only had a plain index on series_id, so on freshly-created databases every episode insert failed — imported series ended up with metadata but no episodes and no EZTV torrents. Added composite uniqueIndex 'idx_episode_unique' so AutoMigrate creates the constraint (self-heals existing empty DBs on startup).