64 bit Image Atomics

[atlv24]

Connections
Fixes #5009
Depends on #6706
Ultimately for bevy meshlets pipeline bevyengine/bevy#10164

Description
Adds 64 bit image atomics to Vulkan, DirectX, and Metal backends. Emulates using RG32Uint on platforms where R64Uint is not available (directX, metal).

Testing
naga tests and runtime tests are included

Checklist

• Run cargo fmt.
• Run cargo clippy. If applicable, add:
  • --target wasm32-unknown-unknown
  • --target wasm32-unknown-emscripten
• Run cargo xtask test to run tests.
• Add change to CHANGELOG.md. See simple instructions inside file.

[jimblandy]

@atlv24 Earlier today you asked me for a suggestion about the texture usages, and a review of the tests. I've posted those now. Is there anything else you need before breaking this up into independent commits for review?

[atlv24]

@jimblandy I've broken it into independent commits already, thanks for the feedback. I've implemented the texture usage stuff, now im working on the tests. :D

[cwfitzgerald]

Looking at the wgpu side:

What would prevent you from doing atomics on an image without the image atomics flag set?

[atlv24]

What would prevent you from doing atomics on an image without the image atomics flag set?

The naga validator currently only permits image atomic operations on the r64uint texture format, and only when the feature is available. No provisions were made for other texture formats yet

[cwfitzgerald]

I mean the texture creation flag - I believe if you don't include the flag on texture creation it'll still you do atomics on it, as those pieces of data never touch each other.

[atlv24]

@cwfitzgerald i have split this into two PRs: #6706 adds image atomics without any of the 64 bit stuff, this one adds the 64 bit stuff. Only the second commit on this PR is relevant to it, as this PR's branch is based off of the other's, so it includes its commits.