Add iOS and Android platform for Silk.NET.WebGPU.Native.WGPU

[xtuzy]

Summary of feature

Curret Silk.NET.WebGPU.Native.WGPU only support desktop, but wgpu-native support iOS and Android, hope Silk.NET.WebGPU.Native.WGPU also support them.

Comments

Does this have a proposal?

Check the documentation/proposals folder. If it doesn't have one, you may need to create one if you're making massive breaking changes.