Add a new pass in eevee
this pass will render a number of spheres
- uses DRW_viewport_matrix_override_set to set the camera to a default location
- uses a copy of the DefaultLitPass to render the 2 spheres + color palette
- uses backculling so no depth check is needed.
- render it during fx (or after)
- use GPU_framebuffer_viewport_set to render the spheres in the corner
- before rendering set num_lights to 0 so no shadows and lights are calculated during this call.
- when pressing N and transparency is turned on, the lookdev balls should slide with the sidebar
- rendering the background should be an option
- option to disable the lights completely
- ~~default diffuse ball should be less shiny~~