Orphan detector: add normalized tag matching that strips parentheticals
and brackets (feat. X, [FLAC 16bit], etc.) and tries first-artist-only
for comma-separated artists. Prevents false orphan flags for tracks
like "The Mountain (feat. Dennis Hopper...)" that exist in DB as
"The Mountain". All lookups remain O(1) set operations.
Orphan fix: replace auto-delete with user choice prompt. Single Fix
and Fix All both show modal asking "Move to Staging" or "Delete".
Move to Staging relocates file to import staging folder for proper
re-import with metadata matching. Fix action flows through API
endpoint → repair_worker.fix_finding → _fix_orphan_file handler.
Staging path uses docker_resolve_path for container compatibility.