onAppStateVariableAdded method
Update the graph when an app state variable is added.
Implementation
void onAppStateVariableAdded(String varKey) {
final varNodeId = NodeIds.appStateVar(varKey);
if (!graph.hasNode(varNodeId)) {
graph.addNode(
DependencyNode(id: varNodeId, type: DependencyNodeType.appState),
);
}
}