Add cxyz Android project structure and initial configuration

- Introduced a new Flutter project for the cxyz Android manga/comic reader, including essential files such as pubspec.yaml, AndroidManifest.xml, and Gradle configuration.
- Added .gitignore files to exclude unnecessary files and directories for both the main project and Android-specific files.
- Implemented initial README.md with project description, features, setup instructions, and API details for ComicLand, MangaRead, and MangaTown.
- Configured analysis options and dependencies in pubspec.yaml to support Flutter development.
- Established a pnpm workspace and lockfile for dependency management.
- Included various Android resources such as icons, styles, and launch backgrounds for a complete application setup.

cxyz-android/test/widget_test.dart

@@ -0,0 +1,12 @@
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:cxyz_android/main.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+
+void main() {
+  testWidgets('App builds', (tester) async {
+    await tester.pumpWidget(const ProviderScope(child: CxyzApp()));
+    // Catalog app bar title from ComicLand source.
+    expect(find.text('ComicLand'), findsOneWidget);
+  });
+}