Add examples for WebGPU rendering via the embedded wgpu-native bindings

[rdw-software]

There's many out there which could be ported. For example:

• https://github.com/samdauwe/webgpu-native-examples
• Those from https://eliemichel.github.io/LearnWebGPU/
• Or from https://sotrh.github.io/learn-wgpu
• https://github.com/cwoffenden/hello-webgpu
• Search Google, there's plenty more