refactor: LLM Compare komplett entfernt, Video/Voice/Alerts Sidebar hinzugefuegt

- LLM Compare Seiten, Configs und alle Referenzen geloescht
- Kommunikation-Kategorie in Sidebar mit Video & Chat, Voice Service, Alerts
- Compliance SDK Kategorie aus Sidebar entfernt

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

website/components/admin/AdminLayout.tsx

@@ -108,16 +108,6 @@ const navigation: NavItem[] = [
     ),
     description: 'Universitaets-Crawling Orchestrator',
   },
-  {
-    name: 'LLM Vergleich',
-    href: '/admin/llm-compare',
-    icon: (
-      <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-        <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 3v2m6-2v2M9 19v2m6-2v2M5 9H3m2 6H3m18-6h-2m2 6h-2M7 19h10a2 2 0 002-2V7a2 2 0 00-2-2H7a2 2 0 00-2 2v10a2 2 0 002 2zM9 9h6v6H9V9z" />
-      </svg>
-    ),
-    description: 'KI-Provider Vergleich',
-  },
   {
     name: 'Daten & RAG',
     href: '/admin/rag',