Add direct usage support for gl_DrawID (#8594)

- [x] Add `gl_DrawID` property declaration in
`source/slang/glsl.meta.slang` similar to `gl_BaseVertex` and
`gl_BaseInstance`
- [x] Ensure it maps to `SV_DrawIndex` semantic
- [x] Add extension requirements in `slang-ir-glsl-legalize.cpp` (GLSL
460 and GL_ARB_shader_draw_parameters)
- [x] Create test case to verify SPIRV output contains `DrawIndex`
decoration
- [x] Run formatting script before committing
- [x] Verify existing tests still pass
- [x] Remove accidentally committed temp files (1.glsl, 3.spv-asm)
- [x] Update .gitignore to prevent similar files from being committed

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<details>

<summary>Original prompt</summary>

> 
> ----
> 
> *This section details on the original issue you should resolve*
> 
> <issue_title>Missing direct usage support for gl_DrawID</issue_title>
> <issue_description># Problem Description
> Because DirectX does not have support for DrawIndex like vulkan does,
i add the support in d3d12 by emulating it and storing it in a root
constant. In vulkan though, i should be able to use it directly, but
because now i store it as a global variable, i cannot use the
SV_DrawIndex semantic either.
> 
> # Preferred Solution
> I'd like to be able to use gl_DrawID like you how can use
gl_BaseVertex and gl_BaseInstance.
> </issue_description>
> 
> <agent_instructions>You can just edit glsl.meta.slang and add a
declaration for gl_DrawID in a similar way to gl_BaseVertex, and map it
to SV_DrawIndex.
> 
> Create a `//TEST:SIMPLE(filecheck=SPIRV): -target spirv` test case,
and use filecheck to verify the output contains the correct SPIRV
`DrawIndex` decoration.</agent_instructions>
> 
> ## Comments on the Issue (you are @copilot in this section)
> 
> <comments>
> </comments>
> 


</details>
Fixes shader-slang/slang#8548

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