Adds a business to your pipeline, taking a snapshot of its Google listing. Needed parameters: request body with the place_id returned by the search endpoint. Purpose: start working a business. A place_id belongs to one agency at a time: while it is in your pipeline nobody else can add it, and it is released when you delete it. Returns 409 when the business is already yours, when it is reserved by another agency, or when your pipeline is full.