- Updated the `RejectPaymentRequestCommandHandler` to immediately suspend user configs if a payment request is rejected and no other pending subscription requests exist. - Introduced `SuspendIfStillUnpaidAsync` method to handle the logic for suspending configs based on the user's billing status. - Enhanced the `MarkPaymentSentCommandHandler` to protect configs during the payment confirmation process, ensuring users remain active while awaiting admin approval. - Refactored `BillingConfigResumer` to include methods for protecting and suspending configs, improving the overall billing management flow. - Updated tests to cover new behaviors and ensure proper functionality in various scenarios related to payment requests and config management.