fix: remove effects count from effects header

- Remove '(N)' count display from effects bar header
- Effect names are already shown in EffectDevice component:
  - Collapsed: vertical text label
  - Expanded: header with full name
- Cleaner header appearance

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

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

components/tracks/TrackList.tsx

@@ -440,9 +440,6 @@ export function TrackList({
                       {/* Effects Header - Collapsible */}
                       <div className="relative flex items-center gap-2 px-3 py-1.5 bg-muted/50 border-b border-border/30">
                         <span className="text-xs font-medium">Effects</span>
-                        <span className="text-xs text-muted-foreground">
-                          ({track.effectChain.effects.length})
-                        </span>
 
                         {/* Show/hide toggle - Positioned absolutely on the right */}
                         <Button