Retrieves a single assistant by its ObjectId. Requires admin or super user privileges. The response includes populated user_data (email, fname, lname, institution, accountType), institution_data (name, ainame, status, picture), and account_data (name, status) objects. For non-super users viewing system assistants (user=null), the instructions field is omitted.
JWT token passed in x-access-token header
The ObjectId of the assistant to retrieve