Abilty to create a user via the CLI

I am working on making Zoph available as a FreedomBox app.

For this it would be useful to automatically add the FreedomBox user as a Zoph user, as part of the Freedombox App setup.

I tried simply adding the user to the database, but although this works at a very basic level it does not create any Preferences for the user. Going further without changes being properly in Zoph is likely to cause problems in the future, so please could you add the ability to add a user via the CLI ? There should probably be a flag to indicate if they are an admin user or not.