**Note:** This is an adoption of @Shfty 's adoption (#8131) of #3996!
All I've done is updated the branch and run the docs CI.
> **Note:** This is an adoption of #3996, originally authored by
@molikto
>
> # Objective
> Allow use of `wgpu::Features::SPIRV_SHADER_PASSTHROUGH` and the
corresponding `wgpu::Device::create_shader_module_spirv` for SPIR-V
shader assets.
>
> This enables use-cases where naga is not sufficient to load a given
(valid) SPIR-V module, i.e. cases where naga lacks support for a given
SPIR-V feature employed by a third-party codegen backend like
`rust-gpu`.
>
> ## Solution
> * Reimplemented the changes from [Spirv shader
bypass #3996](https://github.com/bevyengine/bevy/pull/3996), on account
of the original branch having been deleted.
> * Documented the new `spirv_shader_passthrough` feature flag with the
appropriate platform support context from [wgpu's
documentation](https://docs.rs/wgpu/latest/wgpu/struct.Features.html#associatedconstant.SPIRV_SHADER_PASSTHROUGH).
>
> ## Changelog
> * Adds a `spirv_shader_passthrough` feature flag to the following
crates:
>
> * `bevy`
> * `bevy_internal`
> * `bevy_render`
> * Extends `RenderDevice::create_shader_module` with a conditional call
to `wgpu::Device::create_shader_module_spirv` if
`spirv_shader_passthrough` is enabled and
`wgpu::Features::SPIRV_SHADER_PASSTHROUGH` is present for the current
platform.
> * Documents the relevant `wgpu` platform support in
`docs/cargo_features.md`
---------
Co-authored-by: Josh Palmer <1253239+Shfty@users.noreply.github.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>