412b9e37eb
Operator decision: the enricher is canonical. No MBID still runs the provider chain (name-based providers — Deezer/Last.fm — resolve without an MBID); if every provider returns ErrNotFound the row settles cover/artist source 'none' at the current sources version (re-eligible only when the registered provider set changes). It does NOT skip-and-leave-NULL. The two _NoMBID_LeavesNull tests predated the name-based providers (0020 slice) and asserted the old skip→NULL contract. Updated: - TestEnrichArtist_NoMBID_SettlesNone: stub now returns ErrNotFound (realistic MBID-only-provider-with-empty-MBID), expect source 'none'. - TestEnrichAlbum_NoSidecarNoMBID_SettlesNone: empty registry → allWere404 stays true → expect 'none'. Last failing cluster from the CI-integration initiative; suite should now be fully green. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>