Automatically include used capabilities when covered by vulkan target version spec

[LegNeato]

Discussed in #385

^{Originally posted by nazar-pc September 15, 2025}
I'm getting the following error:

error: error:0:0 - Operand 3 of Decorate requires one of these capabilities: Kernel GroupNonUniform 
         OpDecorate %subgroup_id BuiltIn SubgroupId

If my understanding is correct, this capability is already included by default in spirv-unknown-vulkan1.3 target that I'm using.

Is this a bug in rust-gpu, spirv-opt or am I missing something?

[LegNeato]

@nnethercote This looks like a reasonable first bug as well.

[Firestar99]

In #388 I described a new idea on how to handle capabilities, which would implicitly solve this issue as well. If we're about to refactor our capability system for this, we should at least consider whether we want to head in that direction as well.