- let DrawingSettings carry an optional shaderPassName across managed and native scene draw APIs
- allow RenderObjectsRendererFeature to author explicit ForwardLit or Unlit scene draws
- exercise the new scene draw pass selection seam in the project render pipeline probe
- add a managed DrawingSettings seam for scene draw authoring
- let builtin forward scene draws use an override material when provided
- wire DrawObjectsPass and RenderObjectsRendererFeature through the new settings
