In Tableau 10.5 there is now a new feature that allows to make nested projects https://www.tableau.com/about/blog/2017/12/get-ready-tableau-105-projects-within-project-78906.
But here in TSC the ProjectItem does not contain any properties that can show where the project is (is it root or is it subproject).
Good idea is to add parent_project attribute to the ProjectItem.
Is this possible and is this requires to change Tableau API because just now I can't find related method in Tableau API.