Improve video sharing functionality and page meta tags

Update `bunny-video-modal.tsx` to support custom share domains and modify `VideoPage.tsx` to dynamically update meta tags (title, description, Open Graph, Twitter Card) for enhanced social sharing, using `VITE_SHARE_DOMAIN` environment variable for custom domain configuration.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 074b0e4c-6171-43bd-aa98-f9e04623ca14
Replit-Commit-Checkpoint-Type: full_checkpoint
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client/src/components/bunny-video-modal.tsx

@@ -111,7 +111,9 @@ export default function BunnyVideoModal({ video, isOpen, onClose, onEdit, videos
 
   const getShareUrl = () => {
     if (!video?.id) return window.location.origin;
-    return `${window.location.origin}?video=${video.id}`;
+    // Use custom domain if set, otherwise current domain
+    const baseUrl = import.meta.env.VITE_SHARE_DOMAIN || window.location.origin;
+    return `${baseUrl}/video/${video.id}`;
   };
 
   const copyToClipboard = async () => {