Two bugs surfacing the same user-reported symptom: a Vaiana OST
track ("Where You Are" by Christopher Jackson) wouldn't match against
a Plex/Emby library because the album sits under the album artist
(Lin-Manuel Miranda).
Bug 1: the data was already there but scoring ignored it. The DB
schema has a tracks.track_artist column, the scanner populates it
from Plex's originalTitle and Jellyfin's ArtistItems[0], and the SQL
WHERE clause already searches it — but _rows_to_tracks dropped the
column on its way to the Python object, and _calculate_track_confidence
only scored against the album-artist JOIN. Candidates whose track-
artist matched got returned by the search and then immediately
filtered out by the low confidence score.
Fix: _rows_to_tracks now propagates row['track_artist'] onto the
returned object, and _calculate_track_confidence takes the better of
(album-artist similarity, track-artist similarity) so soundtracks
match through whichever credit the search query carries.
Bug 2: the album-aware fallback path constructed DatabaseTrack with
kwargs the dataclass doesn't accept (artist_name, album_title,
server_source). Every row TypeError'd, the outer except swallowed it
silently, and the fallback never matched anything since the column
was added — invisible because nothing logged it.
Fix: build DatabaseTrack with valid fields and attach the joined
columns afterwards, the same pattern _rows_to_tracks uses.
Adds 6 regression tests covering: track-artist match (the OST case),
album-artist still matches, scorer takes the better of the two,
defensive handling for tracks without track_artist, search-path
attribute propagation, and the previously-dead album-aware fallback.