Here we're squash-merging a branch that adds a new cli tool and some basic APIs for manipulating the data format of virtual branches as used by the frontend.
* simple cli for showing data, including vbranches
* can set and show the remote target default
* basic list, new and move in API for frontend
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Co-authored-by: Kiril Videlov <kiril@videlov.com>
Co-authored-by: Nikita Galaiko <nikita@galaiko.rocks>
