When Navidrome has a stale index (e.g. file was renamed from
'01 - Idea 10.mp3' to '01 - Gibran Alcocer - Idea 10.mp3'),
_findFileInDir now falls back to the original file's directory
and matches by track-number prefix ('01 - ') so the renamed file
is found even without a Navidrome rescan.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>