feat: add vehicle mileage statistics

vehicle-data-platform/apps/web/src/v2/pages/StatisticsPage.test.tsx

@@ -0,0 +1,30 @@
+import { QueryClient, QueryClientProvider } from '@tanstack/react-query';
+import { cleanup, render, screen, waitFor } from '@testing-library/react';
+import { afterEach, expect, test, vi } from 'vitest';
+import { MemoryRouter } from 'react-router-dom';
+import StatisticsPage from './StatisticsPage';
+
+const mileageStatistics = vi.hoisted(() => vi.fn());
+vi.mock('../../api/client', () => ({ api: { mileageStatistics } }));
+
+afterEach(() => { cleanup(); mileageStatistics.mockReset(); });
+
+test('shows distinct period and latest fleet mileage metrics with exact daily evidence', async () => {
+  mileageStatistics.mockResolvedValue({
+    dateFrom: '2026-07-01', dateTo: '2026-07-14', vehicleCount: 2, recordCount: 2, sourceCount: 2,
+    periodMileageKm: 193.3, fleetLatestMileageKm: 168723.9, averageMileagePerVin: 96.65, averageDailyMileageKm: 96.65,
+    trend: [{ date: '2026-07-14', mileageKm: 193.3, vehicles: 2 }],
+    ranking: [{ vin: 'LTEST000000000001', plate: '粤A12345', mileageKm: 104.6, latestMileageKm: 119925, activeDays: 1 }],
+    asOf: '2026-07-14 13:20:00', evidence: 'production mileage evidence'
+  });
+  const client = new QueryClient({ defaultOptions: { queries: { retry: false } } });
+  render(<QueryClientProvider client={client}><MemoryRouter><StatisticsPage /></MemoryRouter></QueryClientProvider>);
+
+  expect((await screen.findAllByText('193.3 km')).length).toBeGreaterThan(0);
+  expect(screen.getByText('168,723.9 km')).toBeInTheDocument();
+  expect(screen.getByText('按车辆与自然日去重')).toBeInTheDocument();
+  expect(screen.getByText('粤A12345')).toHaveAttribute('href', '/vehicles/LTEST000000000001');
+  expect(screen.getByRole('img', { name: '每日行驶里程趋势图' })).toBeInTheDocument();
+  await waitFor(() => expect(mileageStatistics).toHaveBeenCalledTimes(1));
+  expect(mileageStatistics.mock.calls[0][0].get('dateFrom')).toMatch(/^\d{4}-\d{2}-\d{2}$/);
+});