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/ntfy_drain_test.dart

@@ -0,0 +1,34 @@
+import 'package:flutter_test/flutter_test.dart';
+
+/// Mirrors DownloadQueue session drain gating used in `_pump`.
+bool shouldNotifyQueueDrained({
+  required bool sessionHadWork,
+  required int queuedRemaining,
+}) {
+  return sessionHadWork && queuedRemaining == 0;
+}
+
+void main() {
+  group('queue drained gating', () {
+    test('does not fire when no work was processed', () {
+      expect(
+        shouldNotifyQueueDrained(sessionHadWork: false, queuedRemaining: 0),
+        isFalse,
+      );
+    });
+
+    test('fires when work ran and queue is empty', () {
+      expect(
+        shouldNotifyQueueDrained(sessionHadWork: true, queuedRemaining: 0),
+        isTrue,
+      );
+    });
+
+    test('does not fire while items remain', () {
+      expect(
+        shouldNotifyQueueDrained(sessionHadWork: true, queuedRemaining: 2),
+        isFalse,
+      );
+    });
+  });
+}