Improve transactionality, align invoice model with frontend

frontend/src/lib/api.ts

@@ -106,12 +106,22 @@ export type Tenant = {
 
 export type Invoice = {
   id: string
-  customer: string
-  status: string
-  amount_due: number
-  currency: string
+  tenant_pubkey: string
+  amount: number
   period_start: number
   period_end: number
+  created_at: number
+  paid_at: number | null
+  voided_at: number | null
+}
+
+// The backend models an invoice's lifecycle as timestamps rather than a status
+// field, so derive the display status from them: paid once paid_at is set, void
+// once voided_at is set, otherwise still open.
+export function invoiceStatus(invoice: Pick<Invoice, "paid_at" | "voided_at">): "open" | "paid" | "void" {
+  if (invoice.paid_at != null) return "paid"
+  if (invoice.voided_at != null) return "void"
+  return "open"
 }
 
 export type Activity = {

frontend/src/lib/hooks.ts

@@ -9,6 +9,7 @@ import {
   reactivateRelay,
   getRelay,
   getTenant,
+  invoiceStatus,
   listRelayActivity,
   listRelays,
   listTenantInvoices,
@@ -141,7 +142,7 @@ export async function tenantNeedsPaymentSetup(): Promise<boolean> {
 export async function getLatestOpenInvoice(): Promise<Invoice | null> {
   const invoices = await listTenantInvoices(account()!.pubkey)
   const open = invoices
-    .filter(inv => inv.status === "open" && inv.amount_due > 0)
+    .filter(inv => invoiceStatus(inv) === "open" && inv.amount > 0)
     .sort((a, b) => b.period_start - a.period_start)
   return open[0] ?? null
 }