Introduce Tabby Buy-Now-Pay-Later integration: add Tabby config entries (secret/public key, merchant code, mode, currency) to config/nafezly-payments.php; implement TabbyPayment class with pay, verify and capture logic using Tabby API (checkout creation, status check, capture); and register TabbyPayment in the service provider. Handles response parsing, error/rejection messaging, and uses VERIFY_ROUTE_NAME for return URLs.