rendering: document managed srp v1 boundaries

managed/XCEngine.ScriptCore/Rendering/Core/ScriptableRenderContext.cs

@@ -2,6 +2,9 @@ using XCEngine;
 
 namespace XCEngine.Rendering
 {
+    // SRP v1 managed recording surface. Scene recording still delegates to the
+    // native SceneDrawBackend, and raster-pass recording is limited to the
+    // fullscreen PostProcess / FinalOutput stages.
     public sealed class ScriptableRenderContext
     {
         private readonly ulong m_nativeHandle;
@@ -38,6 +41,9 @@ namespace XCEngine.Rendering
                     .Rendering_ScriptableRenderContext_GetDepthTargetHandle(
                         m_nativeHandle));
 
+        // Records the default native scene sequence for MainScene or explicit
+        // scene-pass-request stages. This does not replace the native scene
+        // extraction / culling / draw backend.
         public bool RecordScene()
         {
             return RecordBeforeOpaqueInjection() &&
@@ -241,6 +247,9 @@ namespace XCEngine.Rendering
                         name));
         }
 
+        // SRP v1 wrapper over managed fullscreen raster requests. Commit only
+        // succeeds on fullscreen sequence stages and the execution kinds remain
+        // limited to the built-in fullscreen pass family.
         public RenderGraphRasterPassBuilder AddRasterPass(
             string passName)
         {