Format Code and Add Format Checks to CI (#643)

* Remove unused lib/generated/i18n.dart

* Use `fvm dart format .`

* Add contributing guidelines

* Enforce dart format

* Add `dart format off` directive to generated files

CONTRIBUTING.md

@@ -0,0 +1,50 @@
+# Contributing to InvenTree App
+
+Thank you for considering contributing to the InvenTree App! This document outlines some guidelines to ensure smooth collaboration.
+
+## Code Style and Formatting
+
+### Dart Formatting
+
+We enforce consistent code formatting using Dart's built-in formatter. Before submitting a pull request:
+
+1. Run the formatter on your code:
+   ```bash
+   fvm dart format .
+   ```
+
+2. Our CI pipeline will verify that all code follows the standard Flutter/Dart formatting rules. Pull requests with improper formatting will fail CI checks.
+
+### General Guidelines
+
+- Write clear, readable, and maintainable code
+- Include comments where necessary
+- Follow Flutter/Dart best practices
+- Write tests for new features when applicable
+
+## Pull Request Process
+
+1. Fork the repository and create a feature branch
+2. Make your changes
+3. Ensure your code passes all tests and linting
+4. Format your code using `fvm dart format`
+5. Submit a pull request with a clear description of the changes
+6. Address any review comments
+
+## Development Setup
+
+1. Ensure you have Flutter installed (we use Flutter Version Management)
+2. Check the required Flutter version in the `.fvmrc` file
+3. Install dependencies with `fvm flutter pub get`
+4. Run tests with `fvm flutter test`
+
+## Reporting Issues
+
+When reporting issues, please include:
+- Clear steps to reproduce the issue
+- Expected behavior
+- Actual behavior
+- Screenshots if applicable
+- Device/environment information
+
+Thank you for contributing to the InvenTree App!