♿️(frontend) mark pagination indicators as decorative for screen readers

Hide pagination dot indicators from screen readers using aria-hidden
to prevent noisy output when dots are purely visual decorations.

Improves accessibility by removing redundant announcements
while maintaining visual pagination cues for sighted users.

src/frontend/src/features/rooms/livekit/components/controls/PaginationIndicator.tsx

@@ -23,7 +23,7 @@ export const PaginationIndicator: (
   })
 
   return (
-    <div ref={ref} className="lk-pagination-indicator">
+    <div ref={ref} className="lk-pagination-indicator" aria-hidden="true">
       {bubbles}
     </div>
   )