feat: add padding to bottom of SequencerCanvas and TrackControls for improved layout

src/components/sequencer/SequencerCanvas.tsx

@@ -280,7 +280,7 @@ export const SequencerCanvas = forwardRef<HTMLDivElement, SequencerCanvasProps>(
         className="flex-1 min-h-0 min-w-0 overflow-auto"
         onScroll={handleTracksScroll}
       >
-        <div style={{ width: `${totalWidth}px`, minWidth: `${totalWidth}px` }}>
+        <div style={{ width: `${totalWidth}px`, minWidth: `${totalWidth}px`, paddingBottom: '52px' }}>
           {tracks.map((track) => (
             <TrackRow
               key={track.id}

src/components/sequencer/TrackControls.tsx

@@ -64,7 +64,7 @@ export const TrackControls = forwardRef<HTMLDivElement, TrackControlsProps>(({
         ref={ref}
         className="flex-1 overflow-y-auto [&::-webkit-scrollbar]:hidden"
         onScroll={onScroll}
-        style={{ scrollbarWidth: 'none', msOverflowStyle: 'none' }}
+        style={{ scrollbarWidth: 'none', msOverflowStyle: 'none', paddingBottom: '52px' }}
       >
         {tracks.map((track) => (
           <div