redesign for settings page

frontend/pweb/lib/pages/roles/widgets/empty_state.dart

@@ -0,0 +1,25 @@
+import 'package:flutter/material.dart';
+
+
+class RolesEmptyState extends StatelessWidget {
+  final String label;
+
+  const RolesEmptyState({
+    super.key,
+    required this.label,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+    return Center(
+      child: Padding(
+        padding: const EdgeInsets.symmetric(vertical: 32),
+        child: Text(
+          label,
+          style: theme.textTheme.bodyMedium,
+        ),
+      ),
+    );
+  }
+}