Create a contact

POST/v1/contacts

Creates a contact. `full_name` and `phone_number` are required. Optional fields include `email`, `source`, `type`, `company_name`, `country_name`, `city_name`, `bio`, `additional_attributes`, and `is_blocked`. When omitted, `source` defaults to `api`, `type` defaults to `external`, and `is_blocked` defaults to `false`.