Add WebGPU support

[kkoreilly]

Likely through a wrapper on WebGPU using vGPU and GopherJS.

[kkoreilly]

Web support has been implemented, but we still need WebGPU support for 3D. This will likely not be done in time for v2 because 3D on web is a relatively low-frequency use case and browser support for WebGPU is still about 28% (https://caniuse.com/webgpu).

[kkoreilly]

WebGPU now has much higher support (71.41%), and it seems like the way to go not just for web but also for native platforms, as it will allow us to bypass a ton of Vulkan issues by using https://github.com/rajveermalviya/go-webgpu. We will look into implementing WebGPU now.

[kkoreilly]

To summarize the situation:

• There are two existing Go WebGPU packages: https://github.com/rajveermalviya/go-webgpu and https://github.com/mokiat/wasmgpu
• The first one provides support for WebGPU on all native platforms (macOS, Windows, Linux, iOS, and Android)
• The second one provides support for WebGPU on the web using syscall/js
• Therefore, together these two provide all of the WebGPU support we need
• However, they have slightly different APIs, although they both appear to have the fundamentals intact
• Additionally, both appear to have some extra dependencies or questionable workspace module management decisions
• Therefore, we are probably best off forking the first one and implementing a compatible API with build tags for js in the same package based on the second one
• We could probably merge this back upstream, although it doesn't really appear to be maintained, so we could also just maintain a permanent fork if necessary
• If we are confident we are moving forward with WebGPU, I can add the js WebGPU package to the native one now as described above (this would fix Q: WebAssemble Target possible? rajveermalviya/go-webgpu#250).

[rcoreilly]

ok please proceed with that plan. I will continue to develop using go-webgpu for now.

[gedw99]

Safari now has WebGPU support . Finally can go faster.

[kkoreilly]

I filed rajveermalviya/go-webgpu#268, so the main remaining task for basic WebGPU support on all platforms is the wgpu branch.