WebGPU ToDo tasks

[jadh4v]

Need

Address WebGPU to-do list here:
https://github.com/Kitware/vtk-js/tree/master/Sources/Rendering/WebGPU#todo

ToDo

• Add device.lost handler.
• Create background class to encapsulate, background clear, gradient background, texture background, skybox etc.
• PBR lighting to replace the simple model currently coded.
• Eventually switch to using IBOs and flat interpolation.
• Cropping planes for polydata, image, volume mappers.
• Update widgets to use the new async hardware selector API.
• Add rgb texture support to volume renderer.
• Add lighting to volume rendering.
• Add line zbuffer offset to handle coincident.
• Possibly change the zbuffer equation to be linear float30.

Waiting on fixes/dev in WebGPU spec:

• more cross platform testing and bug fixing, firefox and safari

[jadh4v]

@floryst @martinken
Issue created to track To-Do list of WebGPU features. Using a checklist so it shows 11 subtasks to track partial progress.

[daker]

@jadh4v i have a PR for Cropping planes if you want to check it PR #3464