A basic wgpu gui renderer intended to be used with Neovide based on ideas from Vello and Zed's rendering approaches but with a focus on simplicity.

Some key goals and principles we are trying to follow with this effort:

1. Use wgpu as the graphics library for maximum portability.
2. Define a scene format which can fluently be defined in rust code, and can be serialized to disk for easy rendering and logging.
3. Render the entire scene layer by layer. Within a layer individual components are drawn in declaration order by kind reducing the need for offscreen buffers.
4. Where possible, features of the renderer should be regression tested to ensure that changes do not change the quality of the rendering unless explicitly intended.