Tracks auto-downloaded from the playlist pipeline / wishlist / watchlist landed as
01/1 even though they belong to multi-track albums (wolf/Sokhi; verified live —
Deezer says 'Obelisk' is track 9 of The Grand Mirage, Olives is 3/4, etc.).
Root cause, located in code: discovery doesn't carry a per-track position for
sources whose search/track endpoint omits it (Deezer search, MusicBrainz
recordings — only their ALBUM endpoint has it). detect_album_info_web then set
'track_number': track_info.get('track_number') (= None) and never looked it up
from the album it HAD identified (context.py); the pipeline floored it to 1. The
one helper that does an album lookup only ran for the no-album-context branch and
is gated off by default. Not isolated to Deezer — the gap is source-agnostic.
Fix: when the album is known (album_id present) but the position is missing,
resolve the REAL (track_number, disc_number) from the album's own track list via
the source-agnostic get_album_tracks_for_source — using the album id discovery
already picked (no re-search, no edition guessing). Matches by ISRC -> source
track id -> title. Fail-safe: any miss/error leaves the number untouched, so it
still falls through to the filename exactly as before — never worse than today.
kettui: pure seam core/imports/album_position.resolve_track_position_in_album
(I/O-free, ISRC>id>title priority, skips position-less entries) + a fail-safe
integration wrapper, both covered — 11 tests incl. the 'Obelisk = 9/12' case,
priority resolution, and never-raises-on-fetch-error. 788 import/context/pipeline
tests green, ruff clean.
