QueueTrack gains two additive, serde-default identity keys (the ISRC and
the MusicBrainz recording id) that the listen log stamps; every
constructor in the workspace sets them (Qobuz-backed ones from
Track.isrc, local ones from the scanned tags, the rest None). They are
JOIN keys, not the row identity: numeric ids collide across sources, so
(source, native item id) stays the identity.
Track.audio_info (replaygain_track_gain / peak on DiscoverAudioInfo) is
modelled from the captured search envelopes; no reader yet and no
popularity field (0 in every sample).
cc
vicrodh
ef665dcc5c