Now the user can create tokens
During the sorting phase of the interview, the user can define its own tokens. Implement an according interface to leave the calculation of the circles and the token position correct and well defined.
Backend-wise, create tokens on the go, while giving on the created_by field a dummy user-id (that has to be migrated) that indicates "user during interview created the token".
Moreover, the user can also delete the token, for example by dragging it over an area that appears on-drag of the created token.