entity/

Package coupon holds the billing domain's coupon entity: a discount code with its validity window, usage limits and the plans it applies to.

Package order holds the billing domain's order entities and the rules that travel with them: the order and its details, the status state machine, order numbers, the durable order events and their wake-up channels, and the guest checkout data an order carries until the guest's account exists.

Package payment holds the billing domain's payment method entity and the stored configuration of each gateway it can be bound to.

Package wallet holds the billing domain's money entities: the wallet row (the single source of truth for balance/gift/commission since migration 02144) and withdrawal records (ADR-001 step 5).