feat(srp): add render layer filtering to scene draw

- carry MeshRenderer renderLayer through scene extraction into VisibleRenderItem
- extend native and managed FilteringSettings with renderLayerMask support
- let RenderObjectsRendererFeature author layer-filtered object draws

project/Assets/Scripts/ProjectRenderPipelineProbe.cs

@@ -142,6 +142,8 @@ namespace ProjectScripts
                             overrideRenderQueueRange = true,
                             renderQueueRange =
                                 RenderQueueRange.Opaque,
+                            overrideRenderLayerMask = true,
+                            renderLayerMask = 1u << 0,
                             rendererListType =
                                 RendererListType.Opaque
                         }