PayPal — Added payment method documentation covering one-time payments, authorize/capture/reverse, refunds, payouts, and PayPal Subscriptions. Added Cancel API and Revise API reference pages. See PayPal.
Click to Pay — Added payment method documentation for Secure Remote Commerce (SRC) on the Hosted Payment Page via the Checkout API. See Click to Pay.
OpenAPI spec — Updated openapi.yaml to document paypal and clicktopay payment types, PayPal subscription fields, /rest/cancel and /rest/revise endpoints, payout_email, and available_payment_methods on checkout requests.