Add new pages and improve blog content display functionality

Implement new routes for articles, categories, and individual articles. Update the UI to display articles with improved content rendering, including safe HTML and media embeds. Refactor storage to use a database and add image upload capabilities.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 413891e8-d784-4bea-b9f5-91a5a68316b4
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Event-Id: b96b221e-0ed6-418f-80df-e4670bf5ba4b
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/f209e72a-0939-48fa-84fc-57854de71967/413891e8-d784-4bea-b9f5-91a5a68316b4/cftwqyT
Replit-Helium-Checkpoint-Created: true

client/index.html

@@ -1,8 +1,13 @@
 <!DOCTYPE html>
-<html lang="en">
+<html lang="de" class="dark">
   <head>
     <meta charset="UTF-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1" />
+    <title>news.folx.tv - Folx Music Television News</title>
+    <meta name="description" content="Das Newsportal von Folx Music Television. Aktuelle Nachrichten, Interviews und Hintergrundberichte aus der Welt der Volksmusik und des Schlagers." />
+    <meta property="og:title" content="news.folx.tv - Folx Music Television News" />
+    <meta property="og:description" content="Aktuelle Nachrichten aus der Welt der Volksmusik und des Schlagers." />
+    <meta property="og:type" content="website" />
     <link rel="icon" type="image/png" href="/favicon.png" />
     <link rel="preconnect" href="https://fonts.googleapis.com">
     <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>