fix: address code review findings

- notifier: show artist display names (not internal IDs) in digest; resolve
  names from artist_settings and fall back to ID when unavailable
- notifier: skip sending an empty digest to avoid daily spam
- config: require telegram token/chat_id when enabled
- web: warn loudly when auth is disabled on a non-loopback bind; add HTTP
  server timeouts
- web: treat SetReleaseIgnored "release not found" as benign redirect (0 rows)
- musicbrainz: reject low-score/name-mismatched MBID resolutions instead of
  silently caching the wrong artist
- database: remove dead duplicate err check; harden DSN param appending
- musicbrainz: check rows.Err() after iterating existing releases

internal/database/external_releases.go

@@ -160,7 +160,7 @@ func SetReleaseIgnored(db *DB, rgid string, ignored bool) error {
 		return fmt.Errorf("rows affected: %w", err)
 	}
 	if rowsAffected == 0 {
-		return fmt.Errorf("release not found: %s", rgid)
+		return fmt.Errorf("%w: %s", ErrReleaseNotFound, rgid)
 	}
 
 	return nil