First attempt at a GPU runner

Currently failing with an error I don't understand:

```
wgpu error: Validation Error

Caused by:
  In Device::create_shader_module, label = '...\image_binary.spv'

Shader '...\image_binary.spv' parsing error: InvalidTypeWidth(1)
```

examples/image-binary/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "image-binary"
+version.workspace = true
+authors.workspace = true
+edition.workspace = true
+license.workspace = true
+repository.workspace = true
+
+[dependencies]
+enkou-shaders = { path = "../../enkou-shaders" }
+glam.workspace = true
+spirv-std.workspace = true
+wgpu = { workspace = true, optional = true }
+
+[lints]
+workspace = true

examples/image-binary/src/lib.rs

@@ -0,0 +1,82 @@
+//! # Binary image
+#![cfg_attr(target_arch = "spirv", no_std)]
+use enkou_shaders::camera::Camera;
+use enkou_shaders::chaos_game::ChaosGame;
+use enkou_shaders::rng::xoshiro256starstar_from_seed;
+use enkou_shaders::transform::Transform;
+use enkou_shaders::variation::Variation;
+use glam::{UVec2, UVec4};
+use spirv_std::spirv;
+
+#[cfg(feature = "wgpu")]
+pub use wgpu::*;
+
+const IMAGE_QUALITY: f32 = 1.0;
+const ITERATIONS_FUSE: u32 = 20;
+
+/// Sierpinski Gasket
+#[spirv(compute(entry_point_name = "main_image_binary", threads(1)))]
+pub fn main_image_binary(
+    #[spirv(storage_buffer, descriptor_set = 0, binding = 0)] image_dimensions: &UVec2,
+    #[spirv(storage_buffer, descriptor_set = 0, binding = 1)] transforms: &[Transform],
+    #[spirv(storage_buffer, descriptor_set = 0, binding = 2)] weights: &[f32],
+    #[spirv(storage_buffer, descriptor_set = 0, binding = 3)] variations: &[Variation],
+    #[spirv(storage_buffer, descriptor_set = 0, binding = 4)] camera: &Camera,
+    #[spirv(storage_buffer, descriptor_set = 0, binding = 5)] image_buffer: &mut [UVec4],
+) {
+    // Initialize RNG and run the chaos game
+    let mut rng = xoshiro256starstar_from_seed([4; 32]);
+    let mut chaos_game = ChaosGame::new(&mut rng, transforms, weights, variations);
+
+    // Discard the first few iterations
+    for _ in 0..ITERATIONS_FUSE {
+        chaos_game.next().unwrap();
+    }
+
+    // Plot the remaining points generated by the chaos game
+    let iterations = (image_dimensions.as_vec2().element_product() * IMAGE_QUALITY) as u32;
+    for _ in 0..iterations {
+        let ifs_point = chaos_game.next().unwrap();
+        let pixel_point = camera.transform_point_to_image(ifs_point);
+
+        if let Some(pixel_point) = pixel_point {
+            let pixel_index = pixel_point.y * image_dimensions.x + pixel_point.x;
+            image_buffer[pixel_index as usize] = UVec4::splat(255);
+        }
+    }
+}
+
+#[cfg(feature = "wgpu")]
+pub mod wgpu {
+    const fn bgle(binding: u32, read_only: bool) -> wgpu::BindGroupLayoutEntry {
+        wgpu::BindGroupLayoutEntry {
+            binding,
+            visibility: wgpu::ShaderStages::COMPUTE,
+            ty: wgpu::BindingType::Buffer {
+                ty: wgpu::BufferBindingType::Storage { read_only },
+                has_dynamic_offset: false,
+                min_binding_size: None,
+            },
+            count: None,
+        }
+    }
+
+    pub const BGLE_IMAGE_DIMENSIONS: wgpu::BindGroupLayoutEntry = bgle(0, true);
+    pub const BGLE_TRANSFORMS: wgpu::BindGroupLayoutEntry = bgle(1, true);
+    pub const BGLE_WEIGHTS: wgpu::BindGroupLayoutEntry = bgle(2, true);
+    pub const BGLE_VARIATIONS: wgpu::BindGroupLayoutEntry = bgle(3, true);
+    pub const BGLE_CAMERA: wgpu::BindGroupLayoutEntry = bgle(4, true);
+    pub const BGLE_IMAGE_BUFFER: wgpu::BindGroupLayoutEntry = bgle(5, false);
+
+    pub const BIND_GROUP_IMAGE_BINARY: wgpu::BindGroupLayoutDescriptor = wgpu::BindGroupLayoutDescriptor {
+        label: Some("main_image_binary"),
+        entries: &[
+            BGLE_IMAGE_DIMENSIONS,
+            BGLE_TRANSFORMS,
+            BGLE_WEIGHTS,
+            BGLE_VARIATIONS,
+            BGLE_CAMERA,
+            BGLE_IMAGE_BUFFER,
+        ],
+    };
+}