fix: change timeline track from button to div to avoid focus styles

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/web/src/components/editor/panels/timeline/timeline-track.tsx

@@ -65,7 +65,7 @@ export function TimelineTrackContent({
 	});
 
 	return (
-		<button
+		<div
 			className="size-full"
 			onClick={(event) => {
 				if (shouldIgnoreClick?.()) return;
@@ -75,7 +75,8 @@ export function TimelineTrackContent({
 				event.preventDefault();
 				onTrackMouseDown?.(event);
 			}}
-			type="button"
+			role="button"
+			tabIndex={0}
 		>
 			<div className="relative h-full min-w-full">
 				{track.elements.length === 0 ? (
@@ -109,6 +110,6 @@ export function TimelineTrackContent({
 					})
 				)}
 			</div>
-		</button>
+		</div>
 	);
 }