Flutter-gen

**Bug fix**
- [156](https://github.com/FlutterGen/flutter_gen/pull/156) The Dartdocs generate different strings on Windows and Ubuntu.

**Feature**
- [138](https://github.com/FlutterGen/flutter_gen/pull/138) Generate dartdoc as follows.
dart
/// File path: pictures/chip5.jpg
AssetGenImage get chip5 => const AssetGenImage('pictures/chip5.jpg');
/// Color: 979797
static const Color gray410 = Color(0xFF979797);

- [143](https://github.com/FlutterGen/flutter_gen/pull/143) Support [Rive](https://rive.app/) files type.
yaml
flutter_gen:
integrations:
rive: true

- [150](https://github.com/FlutterGen/flutter_gen/pull/150) Added the --version option for command-line.
shell
% fluttergen --version
FlutterGen v4.1.0

**Bug fix**
- [134](https://github.com/FlutterGen/flutter_gen/pull/134) Added the ability to support the at symbol () in file names.
dart
AssetGenImage get logo2x => const AssetGenImage('assets/images/logo2x.png');

**Development**
- Update to Dart 2.14.4.
- Update to Flutter 2.5.3.
- Replace to renovate.

**Bug fix**
- [134](https://github.com/FlutterGen/flutter_gen/issues/134) Support the at symbol () in file names.
- [139](https://github.com/FlutterGen/flutter_gen/issues/139) Error: Method not found: '$checkedCreate

**Development**
- Replace to flutter_lints.

**Features**
- [BREAKING] Ended support for Non null safety codes.
- Use for `line_length` instead of `lineLength`.


**Development**
- Replace to [Melos](https://pub.dev/packages/melos).
- Add VSCode setting.

- [117](https://github.com/FlutterGen/flutter_gen/issues/117) Update to analyzer 2.0.0.
[flutter_gen_runner (flutter_gen_core) 3.1.2 -> analyzer 2.0.0 workaround](https://github.com/FlutterGen/flutter_gen/issues/121)
yaml
dependency_overrides:
meta: ^1.7.0


- [110](https://github.com/FlutterGen/flutter_gen/pull/110) Replace null safety dart style package.

**Features** & **Bug fix**
- [103](https://github.com/FlutterGen/flutter_gen/pull/103) Add option packageParameterEnabled to control whether to generate package parameter for assets or not.