post https://api.novecore.com/onboarding
Creates an onboarding session and returns the first onboarding step.
If the email address does not already have a login associated with it, the response contains a bearer token for the client to use throughout the onboarding process.
If the email address is already associated with a login, the API returns a 401 error code. The client should then authenticate against the Novecore Authentication Server and call the endpoint again with the bearer token included.