feat: add 3s scroll-pause video auto-play to homepage Signature Menu + update Menu page to 3s

- Duplicated mobile scroll-pause logic (3s timeout) to homepage Signature Menu (using .signature-card + .relative.h-48 structure, with video support added to signatureDishes).
- Updated both /menu and homepage Signature Menu from 2s to 3s pause before playing video on scroll stop.
- Added onMouse handlers for desktop hover consistency on signature cards.
- Maintains posters while scrolling, plays video after 3s pause on item.
- Desktop hover behavior preserved.
- Builds cleanly.

app/menu/page.tsx

@@ -68,7 +68,7 @@ export default function MenuPage() {
     window.scrollTo({ top: 220, behavior: "smooth" });
   };
 
-  // Mobile video auto-play on scroll pause (2s)
+  // Mobile video auto-play on scroll pause (3s)
   useEffect(() => {
     const updateMobile = () => setIsMobile(window.innerWidth < 768);
     updateMobile();
@@ -149,7 +149,7 @@ export default function MenuPage() {
         if (focusedId) {
           playMobileVideo(focusedId);
         }
-      }, 2000);
+      }, 3000);
     };
     window.addEventListener("scroll", onScrollOrTouch, { passive: true });
     window.addEventListener("touchmove", onScrollOrTouch, { passive: true });