How to get a wgpu surface from a canvas?

## Feature Request

I am currently aware that one can render wgpu similar to the example here: https://github.com/DioxusLabs/dioxus/blob/main/examples/wgpu.rs
But the problem is it occupies the entire of the window. You can go far with this approach by adding hacks to only render to a viewport whose position is synced up to the element, by hooking onto scroll, resize events. But its very easy to get it out of sync.

Imho the more correct way would be to directly get the canvas surface and have wgpu render on to it instead. But I can't see ways/examples dioxus currently offers this at the moment.

## Implement Suggestion

Add a way to get webgpu surface in desktop clients