feat(platform): show realtime data freshness

vehicle-data-platform/apps/web/src/test/App.test.tsx

@@ -7626,6 +7626,79 @@ test('refreshes realtime vehicle data from the monitoring workspace', async () =
   expect(realtimeCalls).toBeGreaterThanOrEqual(2);
 });
 
+test('shows realtime freshness status for recently updated and stale vehicles', async () => {
+  window.history.replaceState(null, '', '/#/map');
+  vi.spyOn(globalThis, 'fetch').mockImplementation(async (input) => {
+    const path = String(input);
+    if (path.includes('/api/realtime/vehicles')) {
+      return {
+        ok: true,
+        json: async () => ({
+          data: {
+            items: [
+              {
+                vin: 'VIN-FRESH-001',
+                plate: '粤A新鲜1',
+                protocols: ['GB32960'],
+                sourceStatus: [{ protocol: 'GB32960', online: true, lastSeen: '2999-07-04 17:00:00', hasRealtime: true, hasHistory: true, hasRaw: true, hasMileage: true }],
+                sourceCount: 1,
+                onlineSourceCount: 1,
+                online: true,
+                primaryProtocol: 'GB32960',
+                longitude: 113.2,
+                latitude: 23.1,
+                speedKmh: 30,
+                socPercent: 78,
+                totalMileageKm: 119925,
+                lastSeen: '2999-07-04 17:00:00',
+                bindingStatus: 'bound'
+              },
+              {
+                vin: 'VIN-STALE-001',
+                plate: '粤A超时1',
+                protocols: ['JT808'],
+                sourceStatus: [{ protocol: 'JT808', online: false, lastSeen: '2020-01-01 00:00:00', hasRealtime: true, hasHistory: true, hasRaw: true, hasMileage: true }],
+                sourceCount: 1,
+                onlineSourceCount: 0,
+                online: false,
+                primaryProtocol: 'JT808',
+                longitude: 113.3,
+                latitude: 23.2,
+                speedKmh: 0,
+                socPercent: 50,
+                totalMileageKm: 1000,
+                lastSeen: '2020-01-01 00:00:00',
+                bindingStatus: 'bound'
+              }
+            ],
+            total: 2,
+            limit: 50,
+            offset: 0
+          },
+          traceId: 'trace-test',
+          timestamp: 1783094400000
+        })
+      } as Response;
+    }
+    return {
+      ok: true,
+      json: async () => ({
+        data: { linkHealth: [], kafkaLag: 0, redisOnlineKeys: 0, tdengineWritable: true, mysqlWritable: true, runtime: { requestTimeoutMs: 5000 } },
+        traceId: 'trace-test',
+        timestamp: 1783094400000
+      })
+    } as Response;
+  });
+
+  render(<App />);
+
+  expect(await screen.findByRole('heading', { name: '地图态势' })).toBeInTheDocument();
+  expect(screen.getAllByText('数据新鲜').length).toBeGreaterThan(0);
+  expect(screen.getAllByText('更新超时').length).toBeGreaterThan(0);
+  expect(screen.getByText('超时车辆')).toBeInTheDocument();
+  expect(screen.getByText('1 辆超过 5 分钟未更新。')).toBeInTheDocument();
+});
+
 test('exports current realtime vehicles as CSV', async () => {
   window.history.replaceState(null, '', '/#/realtime?protocol=JT808');
   const createObjectURL = vi.spyOn(URL, 'createObjectURL').mockReturnValue('blob:realtime-export');