fix: ensure track name is always a string in createTrack

Added type checking to prevent event objects from being used as track names.
When onClick handlers pass events, we now explicitly check for string type.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

lib/audio/track-utils.ts

@@ -19,9 +19,12 @@ export function createTrack(name?: string, color?: TrackColor): Track {
   const colors: TrackColor[] = ['blue', 'green', 'purple', 'orange', 'pink', 'indigo', 'yellow', 'red'];
   const randomColor = colors[Math.floor(Math.random() * colors.length)];
 
+  // Ensure name is always a string, handle cases where event objects might be passed
+  const trackName = typeof name === 'string' && name.trim() ? name.trim() : 'New Track';
+
   return {
     id: generateTrackId(),
-    name: name || 'New Track',
+    name: trackName,
     color: TRACK_COLORS[color || randomColor],
     height: DEFAULT_TRACK_HEIGHT,
     audioBuffer: null,
@@ -43,7 +46,9 @@ export function createTrackFromBuffer(
   name?: string,
   color?: TrackColor
 ): Track {
-  const track = createTrack(name, color);
+  // Ensure name is a string before passing to createTrack
+  const trackName = typeof name === 'string' && name.trim() ? name.trim() : undefined;
+  const track = createTrack(trackName, color);
   track.audioBuffer = buffer;
   return track;
 }