fix: convert track name to string in TrackHeader component

Fixed the React error by ensuring track.name is always converted to string in TrackHeader.tsx line 105 where it's rendered.

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

components/tracks/TrackHeader.tsx

@@ -100,9 +100,9 @@ export function TrackHeader({
           <div
             onClick={handleNameClick}
             className="px-2 py-1 text-sm font-medium text-foreground truncate cursor-pointer hover:bg-accent rounded"
-            title={track.name}
+            title={String(track.name || 'Untitled Track')}
           >
-            {track.name}
+            {String(track.name || 'Untitled Track')}
           </div>
         )}
       </div>