Phase 0.2: migrate remaining SVGs to lucide-react icons

frontend/src/components/comm/blocks/ContactCardBlock.tsx

@@ -1,5 +1,6 @@
 import React from 'react';
 import type { MessageBlock } from '@/store/commStore';
+import { ChevronRight } from 'lucide-react';
 
 interface ContactCardBlockProps {
   block: MessageBlock;
@@ -31,20 +32,7 @@ const ContactCardBlock: React.FC<ContactCardBlockProps> = ({ block }) => {
         <p className="text-sm font-medium text-secondary-700 truncate">{contactName}</p>
         <p className="text-xs text-secondary-400">Kontakt anzeigen</p>
       </div>
-      <svg
-        className="w-4 h-4 text-secondary-400 flex-shrink-0"
-        fill="none"
-        viewBox="0 0 24 24"
-        stroke="currentColor"
-        aria-hidden="true"
-      >
-        <path
-          strokeLinecap="round"
-          strokeLinejoin="round"
-          strokeWidth={2}
-          d="M9 5l7 7-7 7"
-        />
-      </svg>
+      <ChevronRight className="w-4 h-4 text-secondary-400 flex-shrink-0" aria-hidden="true" strokeWidth={2} />
     </a>
   );
 };