Shaders: rust-gpu integration to compile shader nodes to WGSL (#3097)

* shaders: shader compilation setup

* nix: use rustc_codegen_spirv.so from nix

* shaders: codegen for per_pixel_adjust shader nodes

* shaders: disable nodes needing bool

* shaders: `#[repr(u32)]` some enums

* shaders: add lint ignores from rust-gpu

* shaders: fix node-macro tests

* gcore-shaders: toml cleanup

* shader-nodes feature: put rust-gpu to wgsl compile behind feature gate

* shaders: fix use TokenStream2

* shaders: allow providing shader externally

* Update iai runner in workflow

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Co-authored-by: Timon Schelling <me@timon.zip>
Co-authored-by: Dennis Kobert <dennis@kobert.dev>

Author: 3 people

.github/workflows/comment-profiling-changes.yaml

@@ -34,12 +34,12 @@ jobs:
         uses: actions/cache@v4
         with:
           path: ~/.cargo/bin/iai-callgrind-runner
-          key: ${{ runner.os }}-iai-callgrind-runner-0.12.3
+          key: ${{ runner.os }}-iai-callgrind-runner-0.16.1
 
       - name: Install iai-callgrind
         if: steps.cache-iai.outputs.cache-hit != 'true'
         run: |
-          cargo install iai-callgrind-runner@0.12.3
+          cargo install iai-callgrind-runner@0.16.1
 
       - name: Checkout master branch
         run: |