BranchNodeId.h header

using ew::core::foundation::BranchNodeId = Id<BranchNodeIdTag>

Stable, globally-unique identity for one node in a branching scene.

Every link between nodes is a pair of these, so a node keeps its incoming and outgoing branches when it is renamed, retyped or moved on the canvas – the same reason story variables are id-identified (see VariableId), and the same defect A3 had to repair in the audience registry.