Hello Arij,
I'm only beginning with popoto, but no, it doesn't seem to be a way in popoto to add or edit nodes. Indeed, the official website states:
Popoto.js is a
JavaScript library built with
D3.js providing a
graph based
search interfaceTherefore, as it is a search interface, it doesn't provide any sort of edition capability AFAIK.
Kind regards,
Bernard