Added Cart Predicate field identifier 'origin'

With the addition of the origin field identifier to Cart Predicates, you can now target the value of the CartOrigin field. This enhancement lets you match against Carts originating from Customers, Merchants, or Quotes. For example, you can use this predicate to create Shipping Methods that are only available for Carts with a specific origin, such as those created by a Merchant.

Changes:

• [API] Added origin predicate field identifier to Cart Predicates.