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

frontend/src/features/workspace/WorkspaceView.tsx

@@ -45,8 +45,6 @@ import {
   Unlock,
   Eye,
   Edit3,
-  Share,
-  Share2,
   Hash,
   User as UserIcon,
 } from 'lucide-react';
@@ -3358,7 +3356,7 @@ export const WorkspaceView: React.FC<WorkspaceViewProps> = ({
                       className="btn-icon"
                       title="Notiz teilen und Berechtigungen"
                     >
-                      <Share className="w-3.5 h-3.5" />
+                      <Users className="w-3.5 h-3.5" />
                     </button>
 
                     <button