Enable videos to autoplay with sound on the platform

Modify the video player to automatically play videos with sound when they are loaded, and adjust the video card component to disable hover previews on mobile devices.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 344ec1e0-1186-4058-bbff-2e9619a7b1e0
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/8cc42625-c1f5-4e43-99bd-77f2c4dedee2/344ec1e0-1186-4058-bbff-2e9619a7b1e0/FgaI1Sc

client/src/components/video-card.tsx

@@ -55,11 +55,13 @@ export default function VideoCard({ video, onClick, className = "", hideOverlay
   // Delay preview start to avoid loading on quick mouse passes
   useEffect(() => {
     if (isHovered) {
-      // Enable preview on both mobile and desktop - shorter delay for mobile
-      const delay = window.innerWidth < 768 ? 300 : 800;
-      hoverTimeoutRef.current = setTimeout(() => {
-        setShowPreview(true);
-      }, delay);
+      // Only enable preview on desktop, disable on mobile
+      if (window.innerWidth >= 768) {
+        const delay = 800;
+        hoverTimeoutRef.current = setTimeout(() => {
+          setShowPreview(true);
+        }, delay);
+      }
     } else {
       if (hoverTimeoutRef.current) {
         clearTimeout(hoverTimeoutRef.current);
@@ -124,8 +126,6 @@ export default function VideoCard({ video, onClick, className = "", hideOverlay
       className={`video-card transition-transform duration-200 hover:scale-[1.02] ${className}`}
       onMouseEnter={() => setIsHovered(true)}
       onMouseLeave={() => setIsHovered(false)}
-      onTouchStart={() => setIsHovered(true)}
-      onTouchEnd={() => setIsHovered(false)}
     >
       {/* Video preview container */}
       <div