chore: initialize Guangya Flutter project

test/widget_test.dart

@@ -0,0 +1,8 @@
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  testWidgets('App starts', (WidgetTester tester) async {
+    // Basic smoke test
+    expect(true, isTrue);
+  });
+}