_Major release introducing Payment Methods, Settlements, and Transaction reporting APIs, along with structured decline code support across payment and checkout flows._

### Added

- API - Payment Methods Resource Added
- Payment Methods - Create Payment Method - POST `/2025-11-01/payment-methods`
- Payment Methods - List Payment Methods - GET `/2025-11-01/payment-methods`
- Payment Methods - Get Payment Method - GET `/2025-11-01/payment-methods/{id}`
- Payment Methods - Create Setup Intent - POST `/2025-11-01/payment-methods/{id}/setup-intents`
- API - Settlements Resource Added
- Settlements - List Settlements - GET `/2025-11-01/settlements`
- Settlements - Get Settlement Detail - GET `/2025-11-01/settlements/{settlementId}`
- Settlements - Get Settlement Reconciliation - GET `/2025-11-01/settlements/{settlementId}/reconciliation`
- API - Transaction Search Added
- Transactions - Search Payment Transactions - GET `/2025-11-01/payments/search`
- API - Payment Intent Resource Added
- Payments - Create Payment Intent - POST `/2025-11-01/payment-intent`
- Refunds - Create Payout Refund (Restricted) - POST `/2025-11-01/refunds/payouts`

### Changed

- Payments - Create Payment Intent now returns 402 responses with structured decline codes (`declineCode`, `declineReason`, `declineClassification`) - POST `/2025-11-01/payment-intent`
- Checkout - Proceed endpoint now returns 402 responses with structured decline codes - POST `/2025-11-01/checkout-sessions/{id}/proceed`
- Customers - Added `externalReference` as an allowed filter on List Customers - GET `/2025-11-01/customers`