refactor(rendering): retain managed pipeline asset runtime per native asset

engine/include/XCEngine/Scripting/Mono/MonoScriptRuntime.h

@@ -22,6 +22,7 @@ namespace XCEngine {
 namespace Scripting {
 
 class ScriptComponent;
+class MonoManagedRenderPipelineAssetRuntime;
 class MonoManagedRenderPipelineBridge;
 class MonoManagedRenderPipelineStageRecorder;
 
@@ -241,6 +242,7 @@ private:
     void SetError(const std::string& error);
 
     friend class MonoManagedRenderPipelineBridge;
+    friend class MonoManagedRenderPipelineAssetRuntime;
     friend class MonoManagedRenderPipelineStageRecorder;
 
     Settings m_settings;