Re-enable the ImageCropper control

[edparitor]

Describe the problem this feature would solve

In the original Uno WCT post https://platform.uno/blog/uno-platform-support-for-the-windows-community-toolkit/
it mentions that
Some notable parts of the toolkit are not working at the moment:
Windows Composition APIs samples, for which the Uno Platform only has very limited support on iOS only.

I've had a quick look at reintroducing the ImageCropper here:
https://github.com/edparitor/Uno.WindowsCommunityToolkit

I progressed to the point that it's no longer using Win2d and is loading a sample image, but I've realised that the last parts are down to the composition API - at least I think they are.

I've also seen that composition api may be on the 3.1 roadmap
unoplatform/uno#670

Describe the solution

Wait for composition API to be implemented and revisit

Describe alternatives you've considered

Re-implement the image cropper in a completely different way for uno - possibly making more use of skia

Additional context & Screenshots