dev.knotless.createRepo

Writes a dev.knotless.repo record under the name given in the account logged in to this appview's web pages, as `knotless repo create` does: public unless asked for private, naming the runners the appview offers for new repositories, and with no branches until the first push. Requires the session cookie the pages' login sets: the appview writes with the session it keeps for that account. Clients holding their own session write the record themselves.