Improve social media sharing image generation for better platform visibility

Add an API endpoint to generate optimized social share images, resolving issues with image display on platforms like WhatsApp.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 2cd2c0bc-434c-4bc9-ad3f-b99d3897a0d1
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/8cc42625-c1f5-4e43-99bd-77f2c4dedee2/2cd2c0bc-434c-4bc9-ad3f-b99d3897a0d1/OdlP8Wj

client/index.html

@@ -11,8 +11,9 @@
     <meta property="og:description" content="Video-Welt von Folx TV – immer bei dir" />
     <meta property="og:type" content="website" />
     <meta property="og:site_name" content="go4.video" />
-    <meta property="og:locale" content="en_US" />
-    <meta property="og:image" content="/go4-video-social-share.png" />
+    <meta property="og:locale" content="de_DE" />
+    <meta property="og:url" content="https://go4video.replit.app/" />
+    <meta property="og:image" content="https://go4video.replit.app/api/social-image" />
     <meta property="og:image:width" content="1200" />
     <meta property="og:image:height" content="630" />
     <meta property="og:image:type" content="image/png" />
@@ -22,7 +23,7 @@
     <meta name="twitter:site" content="@go4video" />
     <meta name="twitter:title" content="go4.video – Video-Welt von Folx TV" />
     <meta name="twitter:description" content="Video-Welt von Folx TV – immer bei dir" />
-    <meta name="twitter:image" content="/go4-video-social-share.png" />
+    <meta name="twitter:image" content="https://go4video.replit.app/api/social-image" />
     
     <!-- Dodatni meta podatki za mobilne naprave -->
     <meta name="application-name" content="go4.video" />