Not easily. Choicescript branching is quite flexible, you can go from label to label, scene to scene, goto/gotoref, gosub and finish.
The only way I can thus think of to accurately map it out would be to scan through every single scene file looking for those navigation commands and slowly populate a node list.
It’s not something I can see being done in real-time as you edit.
@BenSeawalker’s tool is more suited to that sort of thing as it actually groups text blocks under labels from the get go.