refactor(srp): move shadow caster stage selection into managed urp

- add standalone pass asset factories for camera frame stages\n- let managed pipeline assets declare stage pass asset keys\n- make universal renderer data explicitly own the builtin shadow caster stage

engine/src/Rendering/Pipelines/ManagedScriptableRenderPipelineAsset.cpp

@@ -50,13 +50,19 @@ ManagedScriptableRenderPipelineAsset::ResolvePipelineRendererAsset() const {
 
 ScriptableRenderPipelineHostAsset
 ManagedScriptableRenderPipelineAsset::CreateExecutionHostAsset() const {
+    const std::shared_ptr<const ManagedRenderPipelineAssetRuntime> runtime =
+        ResolveManagedAssetRuntime();
     if (const std::shared_ptr<const RenderPipelineAsset> pipelineRendererAsset =
             ResolvePipelineRendererAsset();
         pipelineRendererAsset != nullptr) {
-        return ScriptableRenderPipelineHostAsset(pipelineRendererAsset);
+        return ScriptableRenderPipelineHostAsset(
+            pipelineRendererAsset,
+            runtime);
     }
 
-    return ScriptableRenderPipelineHostAsset();
+    return ScriptableRenderPipelineHostAsset(
+        nullptr,
+        runtime);
 }
 
 std::unique_ptr<RenderPipeline> ManagedScriptableRenderPipelineAsset::CreatePipeline() const {