Add Notifications link to User Management page

- Add quick access button to notification settings in user management header
- Styled to match existing UI gradient theme
- Provides easy navigation from user management to notification configuration

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

app/admin/users/page.tsx

@@ -234,6 +234,14 @@ export default function UsersPage() {
             <h2 className="text-4xl font-bold text-white mb-2">User Management</h2>
             <p className="text-violet-100 text-lg">Verwalte Benutzerkonten und Berechtigungen</p>
           </div>
+          <div className="flex gap-3">
+            <a
+              href="/admin/settings/notifications"
+              className="px-6 py-3 bg-violet-500 text-white rounded-xl hover:bg-violet-600 font-semibold shadow-lg hover:shadow-xl transition-all transform hover:-translate-y-0.5 flex items-center gap-2"
+            >
+              <span>📱</span>
+              <span>Notifications</span>
+            </a>
             <button
               onClick={() => {
                 setFormData({ username: "", email: "", password: "", role: "VIEWER" });
@@ -245,6 +253,7 @@ export default function UsersPage() {
             </button>
           </div>
         </div>
+      </div>
 
       {/* Users Grid */}
       <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-6">