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

---------

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

node-graph/graster-nodes/shaders/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "graphene-raster-nodes-shaders"
+version = "0.1.0"
+edition = "2024"
+description = "graphene raster data format"
+authors = ["Graphite Authors <contact@graphite.rs>"]
+license = "MIT OR Apache-2.0"
+
+[dependencies]
+
+[build-dependencies]
+cargo-gpu = { workspace = true }
+env_logger = { workspace = true }