use checkout payment method for shipping invoices

Load btc details on admin order queries and issue shipping invoices in the same crypto the customer used at checkout.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/src/modules/order/services/OrderService.spec.ts

@@ -222,7 +222,7 @@ describe('OrderService', () => {
             ({
                 id: 'order-1',
                 lines: [{ deliveryMode: DeliveryMode.Manual }],
-                checkoutInvoice: { id: 'checkout-invoice-1', fiatCurrency: 'USD' }
+                checkoutInvoice: { id: 'checkout-invoice-1', fiatCurrency: 'USD', paymentMethod: PaymentMethod.Xmr }
             }) as Order;
 
         it('throws when the order cannot be quoted', async () => {
@@ -300,6 +300,26 @@ describe('OrderService', () => {
             });
             expect(result).toBe(orderExtended);
         });
+
+        it('uses the checkout invoice payment method for shipping invoices', async () => {
+            orderRepo.findOne.mockResolvedValue({
+                ...buildQuotableOrder(),
+                checkoutInvoice: {
+                    id: 'checkout-invoice-1',
+                    fiatCurrency: 'USD',
+                    paymentMethod: PaymentMethod.Btc
+                }
+            });
+
+            await service.setDeliveryCost('order-1', { deliveryCost: 12.5 });
+
+            expect(invoiceService.issueInvoice).toHaveBeenCalledWith({
+                paymentMethod: PaymentMethod.Btc,
+                reason: InvoiceReason.Shipping,
+                contextId: 'order-1',
+                amountFiat: 12.5
+            });
+        });
     });
 
     describe('fulfillManualLine', () => {

backend/src/modules/order/services/OrderService.ts

@@ -15,7 +15,6 @@ import type { InvoiceExtended } from '../../payment/types/InvoiceExtended';
 import type { InvoicePaymentExtended } from '../../payment/types/InvoicePaymentExtended';
 import { InvoiceReason } from '../../payment/types/InvoiceReason';
 import { InvoiceService } from '../../payment/services/InvoiceService';
-import { PaymentMethod } from '../../payment/types/PaymentMethod';
 import { DeliveryMode } from '../../product/types/DeliveryMode';
 import { SetDeliveryCostDto } from '../dto/SetDeliveryCostDto';
 import type { ListOrdersQueryDto } from '../dto/ListOrdersQueryDto';
@@ -99,9 +98,11 @@ export class OrderService {
                 'checkoutInvoice',
                 'checkoutInvoice.payments',
                 'checkoutInvoice.moneroDetails',
+                'checkoutInvoice.btcDetails',
                 'shippingInvoice',
                 'shippingInvoice.payments',
                 'shippingInvoice.moneroDetails',
+                'shippingInvoice.btcDetails',
                 'lines',
                 'lines.manualFulfillment',
                 'discounts',
@@ -244,7 +245,7 @@ export class OrderService {
         }
 
         const shippingInvoice = await this.invoiceService.issueInvoice({
-            paymentMethod: PaymentMethod.Xmr,
+            paymentMethod: order.checkoutInvoice.paymentMethod,
             reason: InvoiceReason.Shipping,
             contextId: orderId,
             amountFiat: deliveryCost