refactor(billing): rebuild payments list as flat invoice list (tauri parity)

Align /admin/my-payments with the tauri /payments source (per user): the list
is now a flat, newest-first list of the tenant's recorded invoices — one row
per invoice — instead of the per-patient aggregation built from Figma.

Backend:
- replace InvoiceRepository::patientPaymentSummary aggregation with
  tenantInvoices/countTenantInvoices (flat, joins patient name/national code).
- InvoiceService::patientPaymentList → tenantInvoiceList.
- BillingController: GET /api/v1/my/billing/patient-payments →
  GET /api/v1/my/billing/payments returning
  { invoice_uuid, patient_uuid, patient_name, national_code, issued_at,
    amount_rials, status } rows.
- node-2 patient invoices endpoint unchanged.

Frontend:
- useMyPayments: usePatientPayments → usePayments (flat PaymentRow).
- MyPaymentsPage columns match tauri DetailT: row #, avatar+name, national
  code, date-time, amount paid, مشاهده (no status column); 'اضافه کردن بیمار'
  links to /admin/patients/new. Filters (national code / status / Jalali date
  range) kept.

Tests + docs/api/billing.md updated. Intentionally omitted tauri extras:
mobile Cards view and the advanced ModalFilter.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

assets/admin/hooks/useMyPayments.test.tsx

@@ -9,7 +9,7 @@ vi.mock('../lib/api', () => ({
 }));
 
 import { api } from '../lib/api';
-import { usePatientPayments, usePatientInvoices } from './useMyPayments';
+import { usePayments, usePatientInvoices } from './useMyPayments';
 
 const get = api.get as ReturnType<typeof vi.fn>;
 
@@ -25,10 +25,10 @@ beforeEach(() => {
 
 describe('useMyPayments', () => {
   it('builds the list URL with all active filters', async () => {
-    renderHook(() => usePatientPayments({ page: 2, national_code: '1744', status: 'paid', from: 100, to: 200 }), { wrapper });
+    renderHook(() => usePayments({ page: 2, national_code: '1744', status: 'paid', from: 100, to: 200 }), { wrapper });
     await waitFor(() => expect(get).toHaveBeenCalled());
     const url = get.mock.calls[0][0] as string;
-    expect(url).toContain('/api/v1/my/billing/patient-payments?');
+    expect(url).toContain('/api/v1/my/billing/payments?');
     expect(url).toContain('page=2');
     expect(url).toContain('national_code=1744');
     expect(url).toContain('status=paid');
@@ -37,7 +37,7 @@ describe('useMyPayments', () => {
   });
 
   it('omits empty filters from the list URL', async () => {
-    renderHook(() => usePatientPayments({ page: 1 }), { wrapper });
+    renderHook(() => usePayments({ page: 1 }), { wrapper });
     await waitFor(() => expect(get).toHaveBeenCalled());
     const url = get.mock.calls[0][0] as string;
     expect(url).not.toContain('national_code=');

assets/admin/hooks/useMyPayments.ts

@@ -2,23 +2,24 @@ import { useQuery } from '@tanstack/react-query';
 import { api } from '../lib/api';
 import type { ApiResponse, PaginatedResponse } from '../lib/api';
 
-/** A derived per-patient payment status shown on the list (node 1). */
-export type PaymentRowStatus = 'paid' | 'unpaid' | 'unsettled';
+/** Two-state invoice status shown on both the list (node 1) and detail (node 2). */
+export type PaymentRowStatus = 'paid' | 'unsettled';
 
-export interface PatientPaymentRow {
+/** One recorded invoice on the flat payments list (node 1). */
+export interface PaymentRow {
+  invoice_uuid: string;
   patient_uuid: string;
   patient_name: string | null;
   national_code: string | null;
-  invoice_count: number;
-  paid_rials: number;
-  remaining_rials: number;
+  issued_at: number;
+  amount_rials: number;
   status: PaymentRowStatus;
 }
 
-export interface PatientPaymentFilters {
+export interface PaymentFilters {
   page: number;
   national_code?: string;
-  status?: string;   // paid | unsettled | unpaid
+  status?: string;   // paid | unsettled
   from?: number;     // unix seconds
   to?: number;       // unix seconds
 }
@@ -44,17 +45,17 @@ export interface PatientInvoicesPayload {
 
 const LIMIT = 20;
 
-/** Node 1 — paginated per-patient payment summary for the current tenant. */
-export function usePatientPayments(filters: PatientPaymentFilters) {
+/** Node 1 — flat, paginated list of the current tenant's recorded invoices. */
+export function usePayments(filters: PaymentFilters) {
   const qs = new URLSearchParams({ page: String(filters.page), limit: String(LIMIT) });
   if (filters.national_code) qs.set('national_code', filters.national_code);
   if (filters.status)        qs.set('status', filters.status);
   if (filters.from)          qs.set('from', String(filters.from));
   if (filters.to)            qs.set('to', String(filters.to));
 
-  return useQuery<PaginatedResponse<PatientPaymentRow>>({
-    queryKey: ['patient-payments', filters],
-    queryFn: () => api.get(`/api/v1/my/billing/patient-payments?${qs.toString()}`),
+  return useQuery<PaginatedResponse<PaymentRow>>({
+    queryKey: ['payments', filters],
+    queryFn: () => api.get(`/api/v1/my/billing/payments?${qs.toString()}`),
   });
 }