Boulder: "all 50 tracks are discovered to Deezer already — it's not using any of that." Right —
the export only checked tracks.deezer_id (library) and ignored the IDs discovery already resolved
and stored in each mirrored track's extra_data. So tracks that were discovered+downloaded but not
separately enriched showed as "not on Deezer" and got dropped.
Adds a per-track waterfall for service export:
- service_id_from_extra_data(track, service): the id discovery already matched, read from
extra_data.matched_data.id — FREE (no API call) and reliable (it's the same id used to mirror
the track). Trusted only when discovered ON the target service (provider == service); a
wing_it_fallback (low-confidence guess) does NOT match here, so it falls through rather than
risk a wrong track in the export.
- resolve_service_track_ids(tracks, service): cache (extra_data) → library stored id → unmatched.
Reports from_cache / from_library / unmatched. _run_service_export now uses this instead of the
artist/title MBID-style resolver.
For Boulder's playlist this means all 50 resolve straight from the cache — full coverage, zero API
calls. (A live confident-search backfill for the genuinely-missing remainder is the optional next
step, gated + thresholded.)
9 new tests: extra_data id only when provider matches + wing_it excluded + bad-json/not-discovered
guards, the cache→library→unmatched waterfall with stat tallies, and _run_service_export resolving
straight from the cache end-to-end. 49 export tests green, ruff clean.