style: replace upload-style share icon with two-person users icon across all views

frontend/src/features/lists/SharedListsView.tsx

@@ -6,7 +6,6 @@ import {
   Check,
   Radio,
   Sparkles,
-  Share,
   X,
   Hash,
 } from 'lucide-react';
@@ -799,7 +798,7 @@ export const SharedListsView: React.FC<SharedListsViewProps> = ({ onRefreshGloba
                   className="btn-icon"
                   title="Liste teilen und Berechtigungen"
                 >
-                  <Share className="w-3.5 h-3.5" />
+                  <Users className="w-3.5 h-3.5" />
                 </button>
               </div>
             );