feat: streamline track and master controls layout consistency

- Streamlined track controls and master controls to same width (240px)
- Fixed track controls container to use full width of parent column
- Matched TrackControls card structure with MasterControls (gap-3, no w-full/h-full)
- Updated outer container padding from p-2 to p-4 with gap-4
- Adjusted track controls wrapper to center content instead of stretching
- Added max-width constraint to PlaybackControls to prevent width changes
- Centered transport control buttons in footer

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

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

components/automation/AutomationHeader.tsx

@@ -69,10 +69,13 @@ export function AutomationHeader({
   return (
     <div
       className={cn(
-        'relative flex items-center gap-2 px-2 py-1 bg-muted/50 border-b border-border/30 flex-shrink-0',
+        'flex items-center gap-2 px-3 py-1.5 bg-muted border-t border-b border-border/30 flex-shrink-0',
         className
       )}
     >
+      {/* Automation label - always visible */}
+      <span className="text-xs font-medium flex-shrink-0">Automation</span>
+
       {/* Color indicator */}
       {color && (
         <div