feat: Implement Windows runner for Flutter application

- Added FlutterWindow class to manage the Flutter view within a Win32 window.
- Created main entry point in main.cpp to initialize and run the Flutter application.
- Implemented utility functions for console attachment and command line argument parsing.
- Added resource management for application icon and manifest.
- Enhanced Win32Window class for DPI awareness and theme management.
- Included necessary headers and resource files for building the Windows runner.

lib/l10n/untranslated.json

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