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/lib/services/reader_zoom.dart

@@ -0,0 +1,32 @@
+import 'package:shared_preferences/shared_preferences.dart';
+
+/// Layout zoom for the in-app reader (`pageWidth = screenWidth * scale`).
+class ReaderZoom {
+  static const prefKey = 'reader_zoom_scale';
+  static const double min = 0.4;
+  static const double max = 1.5;
+  static const double step = 0.1;
+  static const double defaultScale = 1.0;
+
+  static double clamp(double value) {
+    final stepped = (value / step).round() * step;
+    return stepped.clamp(min, max);
+  }
+
+  static Future<double> load() async {
+    final prefs = await SharedPreferences.getInstance();
+    final raw = prefs.getDouble(prefKey);
+    if (raw == null) return defaultScale;
+    return clamp(raw);
+  }
+
+  static Future<void> save(double scale) async {
+    final prefs = await SharedPreferences.getInstance();
+    await prefs.setDouble(prefKey, clamp(scale));
+  }
+
+  static String percentLabel(double scale) {
+    final pct = (clamp(scale) * 100).round();
+    return '$pct%';
+  }
+}