Adjust card sizes and remove excessive advertisements on the homepage

Reduce the aspect ratio of wide article cards from 4/3 to 16/9 and remove standalone ArticleCardAd components from the homepage.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 1f7e7e89-a520-4970-9645-37daadc466dc
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Event-Id: 0edf8dc1-93c0-48f9-aa7d-c5138ea7f0ab
Replit-Helium-Checkpoint-Created: true

client/src/pages/home.tsx

@@ -188,7 +188,7 @@ function WideCard({ article, focalPoints }: { article: Article; focalPoints?: Re
   return (
     <Link href={`/article/${article.slug}`}>
       <div className="relative group cursor-pointer rounded-lg overflow-hidden bg-card border border-card-border h-full" data-testid={`card-wide-${article.id}`}>
-        <div className="relative aspect-[4/3] overflow-hidden">
+        <div className="relative aspect-[16/9] overflow-hidden">
           <img src={thumbUrl(article.coverImage)} alt={article.title} className="w-full h-full object-cover transition-transform duration-500 group-hover:scale-105" style={{ objectPosition: objPos }} loading="lazy" />
           {isVideo && (
             <div className="absolute inset-0 flex items-center justify-center">