add flutter example app test

client/flutter_ui/test/app_shell_test.dart

@@ -0,0 +1,19 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:netbird_flutter_ui/src/app_shell.dart';
+import 'package:netbird_flutter_ui/src/daemon_client.dart';
+
+void main() {
+  testWidgets('renders the status shell', (tester) async {
+    await tester.pumpWidget(
+      NetBirdFlutterApp(
+        client: FakeDaemonClient(daemonAddr: 'tcp://127.0.0.1:41731'),
+      ),
+    );
+
+    await tester.pump();
+
+    expect(find.text('Status'), findsWidgets);
+    expect(find.text('Connect'), findsOneWidget);
+    expect(find.text('Disconnect'), findsOneWidget);
+  });
+}