Add sharing buttons and optimize social media previews for articles

Integrates social sharing buttons into article pages and implements server-side Open Graph meta tags for improved link previews on social platforms. Updates image URLs in gallery data.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 517dfa7b-26ac-463d-a6e1-a58c6df97188
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Replit-Commit-Event-Id: 83d8fce0-d4ba-4eff-b4de-771170e3b028
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client/src/pages/article.tsx

@@ -10,6 +10,7 @@ import Header from "@/components/header";
 import Footer from "@/components/footer";
 import { InArticleAd } from "@/components/adsense";
 import DOMPurify from "dompurify";
+import ShareButtons from "@/components/share-buttons";
 import { useEffect, useMemo } from "react";
 
 const ALLOWED_IFRAME_DOMAINS = [
@@ -199,6 +200,14 @@ export default function ArticlePage() {
               {article.views.toLocaleString()} Aufrufe
             </span>
           </div>
+
+          <div className="mt-4">
+            <ShareButtons
+              url={`${window.location.origin}/article/${article.slug}`}
+              title={article.title}
+              image={article.coverImage ? (article.coverImage.startsWith("http") ? article.coverImage : `${window.location.origin}${article.coverImage}`) : undefined}
+            />
+          </div>
         </div>
 
         {(() => {
@@ -245,6 +254,14 @@ export default function ArticlePage() {
           );
         })()}
 
+        <div className="mt-8 pt-6 border-t border-border">
+          <ShareButtons
+            url={`${window.location.origin}/article/${article.slug}`}
+            title={article.title}
+            image={article.coverImage ? (article.coverImage.startsWith("http") ? article.coverImage : `${window.location.origin}${article.coverImage}`) : undefined}
+          />
+        </div>
+
         <RelatedArticles currentSlug={slug || ""} />
       </main>
       <Footer />