ITreeNodeStatic Interface
A static, expansion-state-free snapshot of a tree node. Used internally by tree providers for structural operations where expansion state is irrelevant (e.g. building the hierarchy map, computing depths, and resolving parent-child relationships).
Difference from ITreeNode
ITreeNode is the full runtime node including reactive isExpanded state. ITreeNodeStatic is a simpler snapshot used during data processing — before expansion state is applied.