Changes to Agent Registration

the response's body type changed from object to string for status 200

removed the required property coldkey from the response with the 200 status

removed the required property hotkey from the response with the 200 status

removed the required property message from the response with the 200 status

removed the required property payment_address from the response with the 200 status

removed the required property registration_id from the response with the 200 status

removed the required property required_amount from the response with the 200 status

removed the required property user_id from the response with the 200 status

added the optional property detail/items/ctx to the response with the 422 status

added the optional property detail/items/input to the response with the 422 status

endpoint added

api path removed without deprecation