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-runner/Cargo.toml

@@ -0,0 +1,27 @@
+[package]
+name = "image-runner"
+version.workspace = true
+authors.workspace = true
+edition.workspace = true
+license.workspace = true
+repository.workspace = true
+
+[dependencies]
+enkou-shaders = { path = "../../enkou-shaders" }
+image-binary = { path = "../image-binary", features = ["wgpu"] }
+
+anyhow.workspace = true
+bytemuck.workspace = true
+futures.workspace = true
+glam = { workspace = true, features = ["u8"] }
+image.workspace = true
+tempfile.workspace = true
+wgpu.workspace = true
+xflags.workspace = true
+
+[build-dependencies]
+anyhow.workspace = true
+cargo-gpu-install.workspace = true
+
+[lints]
+workspace = true