This endpoint is used to create a Program to a user using the program template defined as parameter. An optional arrival date will be used prior.

Set activate to true to start the program immediately. Left out, the program is created as a draft, nobody is notified, and it has to be started from the interface.

Rehiring someone the platform already knows goes through this endpoint too. Look the person up with GET /users?personal_email=... or GET /users?professional_email=..., update their profile with PUT /users/{id} so that the arrival date, contract, office, department and job position match the new period, then call this endpoint.

A program the person has already completed does not prevent a new one. A program of the same template that is still draft or active does, and the call is then rejected with a 409.