Drop support for UWP

[Jklawreszuk]

PR Details

This PR drops support for UWP and it's codebase.

The main reason is that UWP support has been abandoned since .NET 5 and Microsoft recommends to migrate to MS GDK for Xbox consoles.

That said, the last version that targeted .NET 5 version was a very long time ago (4.1.0.1459-beta) and this PR is also intended to avoid unnecessary frustration for new developers over a feature that is long gone.

Types of changes

• [x] Docs change / refactoring / dependency upgrade
• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [x] Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• [x] My change requires a change to the documentation.
• [ ] I have added tests to cover my changes.
• [ ] All new and existing tests passed.
• [ ] I have built and run the editor to try this change out.

[VaclavElias]

This test is missing " I have built and run the editor to try this change out." 🤣

[Jklawreszuk]

@VaclavElias Welp...Testing always takes more time, but if you want to help speed it up, feel free to test it by yourself 😜

[MeharDT]

Should we reconsider this PR in light of .NET 9 adding legacy support for UWP? At the very least it helps us migrate Stride users away from 4.0 and .NET Framework if they want UWP support.

https://devblogs.microsoft.com/ifdef-windows/preview-uwp-support-for-dotnet-9-native-aot/

[Eideren]

@MeharDT I was not aware of this one, you're right, we'll revisit this issue whenever UWP support becomes problematic then

[Jklawreszuk]

I marked PR as draft for now. We'll see what happens next with UWP support