fix(billing): ceil CBE invoice amounts to whole birr

apps/edr-freight-api/src/modules/billing/billing.service.ts

@@ -1191,7 +1191,11 @@ export class BillingService {
       // service branches on a domain-specific reference type.
       referenceType: PaymentReferenceType.SHIPMENT,
       orderRef: invoice.invoiceNumber.replace(/-/g, "_"),
-      amountMinor: Math.round(Number(invoice.balanceAmount)),
+      // Whole birr, always UP. CBE bills this amount verbatim, so it must never
+      // land below the outstanding balance — Math.round would let a .40 balance
+      // settle 0.40 short. Ceil overcharges by <1 birr instead, and the same
+      // ceil in billQuery keeps the quoted and debited amounts identical.
+      amountMinor: Math.ceil(Number(invoice.balanceAmount)),
       currency: invoice.currency,
       reason: `Payment for invoice ${invoice.invoiceNumber}`,
       method: opts.method ?? "TELEBIRR",
@@ -1336,7 +1340,9 @@ export class BillingService {
     });
 
     if (open) {
-      const balance = Math.round(Number(open.balanceAmount ?? open.totalAmount));
+      // Ceil, matching payInvoice — the amount CBE quotes at the counter has to
+      // be the amount the intent was opened for, or /cbe/payment sees a mismatch.
+      const balance = Math.ceil(Number(open.balanceAmount ?? open.totalAmount));
       const expired = open.dueAt && open.dueAt.getTime() < Date.now();
       return {
         stillPayable: balance > 0 && !expired,
@@ -1371,7 +1377,7 @@ export class BillingService {
     return {
       stillPayable: false,
       payerName: latest.company?.name ?? null,
-      currentAmountMinor: Math.round(Number(latest.totalAmount)),
+      currentAmountMinor: Math.ceil(Number(latest.totalAmount)),
       currency: latest.currency,
       paymentReason: `Freight invoice ${latest.invoiceNumber}`,
       reason: closedInvoiceReason(latest.status),