Add scene chain Insta OF demo workflow

README.md

@@ -144,6 +144,9 @@ as one long chain:
    manually into either generation lane, but they are not part of the default
    main path.
 
+A dedicated v2 scene-chain Insta/OF branching demo is available at
+`examples/scene_chain_insta_of_branching_workflow.json`.
+
 ## Loop Nodes
 
 `SxCP For Loop Start` and `SxCP For Loop End` provide a lightweight replacement