Update social media sharing to use dynamic URLs and images

Update client/index.html and client/src/pages/VideoPage.tsx to dynamically set social media meta tags (og:url, og:image, twitter:image) to the current domain and video-specific thumbnails, resolving issues with incorrect sharing previews.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 2cd2c0bc-434c-4bc9-ad3f-b99d3897a0d1
Replit-Commit-Checkpoint-Type: full_checkpoint
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client/src/pages/VideoPage.tsx

@@ -180,9 +180,10 @@ export default function VideoPage() {
         : `Schauen Sie sich "${currentVideo.title}" auf go4.video an. Professionelle Video-Streaming-Plattform mit exklusivem Content von FOLX STADL, Geschichte des Liedes und weiteren Premium-Inhalten.`;
       
       updateMetaTag('og:description', richDescription);
-      // Uporabljan cache-busting parameter za social media refresh
+      // Get the correct domain dynamically and add cache-busting
       const timestamp = new Date().getTime();
-      const socialThumbnail = `${window.location.origin}/api/video-thumbnail/${currentVideo.id}?v=${timestamp}`;
+      const currentDomain = window.location.origin;
+      const socialThumbnail = `${currentDomain}/api/video-thumbnail/${currentVideo.id}?v=${timestamp}`;
       updateMetaTag('og:image', socialThumbnail);
       updateMetaTag('og:image:width', '1200');
       updateMetaTag('og:image:height', '630');