AvaloniaUI/Avalonia ? reverse-engineered prompt

Build me a cross platform .NET UI framework in C# and XAML that lets people make desktop, mobile, and web apps from one codebase. I want it to feel familiar to anyone who has used WPF, with good styling, reusable controls, data binding, and a clean way to structure apps.

Please make it work on Windows, macOS, Linux, iOS, Android, and WebAssembly, and include a few simple sample apps so it is easy to see how everything fits together. If you need to check current docs or patterns online while putting it together, go ahead. I also want the project to be set up so it is easy to build, test, and contribute to, with clear startup docs for new users.