feat: initialize Flutter project with version management

- Initialize Flutter 3.38 project with all platforms
- Add build-time version generation from pubspec.yaml
- Print version to console on app startup
- Create CHANGELOG.md following Keep a Changelog format
- Update .gitignore for Flutter + generated files
- Basic app scaffold with Material 3 theming

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.gitignore

@@ -7,12 +7,17 @@ build/
 pubspec.lock
 
 # Generated files
-*.g.dart
 *.freezed.dart
 *.gr.dart
 *.mocks.dart
 lib/generated_plugin_registrant.dart
 
+# Keep version.g.dart - it's generated but should be committed
+# so CI/CD builds have version info without running the generator
+# Other *.g.dart files (from json_serializable, etc.) are ignored
+lib/**/*.g.dart
+!lib/version.g.dart
+
 # IDE
 .idea/
 *.iml