feat: Minstrel no longer talks to Lidarr: its connection, Delete via Lidarr and the unmonitor options are gone, and the track reports are plain quarantine (M502 #5525)

Migration 0091 drops lidarr_config and renames the quarantine tables, types,
indexes and the history column off the Lidarr name. The Integrations Lidarr
card, the Reports "Delete via Lidarr" action, the merge and remove-track
unmonitor options, the Lidarr audit actions and error codes go, on the
server, web and Android. The README describes acquisition as it is now.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/similarity/worker.go

@@ -6,8 +6,8 @@
 // For recordings it keeps LB's whole answer in listenbrainz_similar_recordings
 // and derives the track_similarity edges from it in SQL, against whatever is
 // in the library at the time (#5296). Matching once at fetch time missed every
-// recording that reached the library afterwards, through Lidarr or an MBID the
-// AcoustID lookup filled in. For artists it stores the in-library matches in
+// recording that reached the library afterwards, through an import or an MBID
+// the AcoustID lookup filled in. For artists it stores the in-library matches in
 // artist_similarity and the rest in artist_similarity_unmatched, as before.
 //
 // Every answer is recorded as a fetch, an empty one included, and the queue
@@ -85,7 +85,7 @@ func (w *Worker) tickOnce(ctx context.Context) error {
 		return err
 	}
 	// Links recordings that reached the library since their seed was fetched:
-	// a scan, a Lidarr import, an MBID from the AcoustID lookup.
+	// a scan, an import, an MBID from the AcoustID lookup.
 	if err := q.ResolveListenBrainzTrackEdges(ctx, nil); err != nil {
 		return fmt.Errorf("resolve similarity edges: %w", err)
 	}