fix: adjust timeline right padding to match scrollbar width

Changed timeline right padding from 240px to 250px to account for the
vertical scrollbar width in the waveforms area, ensuring perfect alignment
between timeline and waveform playhead markers.

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

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

components/timeline/TimeScale.tsx

@@ -219,7 +219,7 @@ export function TimeScale({
   }, []);
 
   return (
-    <div className={cn('relative bg-background', className)} style={{ paddingLeft: '240px', paddingRight: '240px' }}>
+    <div className={cn('relative bg-background', className)} style={{ paddingLeft: '240px', paddingRight: '250px' }}>
       <div
         ref={scrollRef}
         className="w-full bg-background overflow-x-auto overflow-y-hidden custom-scrollbar"