A single and the album it is on stay two files, since each fulfils its own
release in Lidarr, but they are one song to the listener.
- tracks.song_id links copies; the generated song_key (song_id, else the
track's own id) is what they share (migration 0076).
- The resolver links each cross-release group every pass (idempotent; only
with auto-resolve on) and, when a link is new, shares existing likes across
the song and logs them for sync.
- A like or unlike (web and Subsonic) reaches every copy; each change is
logged and published so clients update every heart.
- The Liked list and its count show the song once; Shuffle and the mix writer
take one copy per song.
- A merge keeps the removed copy's song link; "Not the same song" on the
Across releases tab dismisses the group and undoes the link.
Shared plays ("heard via another copy") are left for a later step.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
ListRecentSessionTracks + UpdatePlayEventVector for the vector capture
path inside RecordPlayStarted. LikeTrack switches to :execrows so the
contextual-likes capture can detect insert vs already-exists. Existing
callers updated to ignore the count for now; later tasks consume it.
Three tables keyed on (user_id, entity_id) with liked_at. Per-table
indexes on (user_id, liked_at DESC) for the recently-liked feed.
sqlc queries cover like/unlike/list-rows/count/list-ids per entity.