FORCDK-TREE-005
Thrown by forty-cdk/tree.
[forty-cdk/tree] FORCDK-TREE-005: `cascade` is enabled but no `descendantsOf` descriptor is bound.
Cause
Cascading a check to a subtree needs the descendant values of a node, which only the consumer can supply — the tree never sees unmounted nodes.
Fix
Bind [descendantsOf] to a function returning the descendant values of a node.