feat(srp): add drawing settings override material seam

- 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

project/Assets/Scripts/ProjectRenderPipelineProbe.cs

@@ -139,6 +139,8 @@ namespace ProjectScripts
                                 RenderPassEvent.RenderOpaques,
                             scenePhase =
                                 SceneRenderPhase.Opaque,
+                            overrideMaterialPath =
+                                "Assets/New Material.mat",
                             overrideRenderQueueRange = true,
                             renderQueueRange =
                                 RenderQueueRange.Opaque,