Adjust points and record actions: wrapped request bodies

• Adjust Loyalty Customer Points: wrap the fields in a points object. The customer has to be opted in to the loyalty program; otherwise the call returns 422 with Customer has to be opt in for manual adjustment.
• Record Loyalty Customer Action: wrap the fields in a custom_actions object. action_name has to match a Custom Action campaign in the merchant's loyalty program; otherwise the call returns 422.

The reference schemas now match the request examples, and both 422 responses are documented.

Endpoints affected: Adjust Loyalty Customer Points, Record Loyalty Customer Action.