fix(mileage): skip missing daily mileage in interval totals

src/modules/mileage/mileage-display.test.ts

@@ -0,0 +1,23 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import { monitoringMileageValue, recentMileageStats } from './mileage-display';
+import type { VehicleRecentDay } from './api';
+import type { MonitoringVehicle } from './types';
+
+const day = (dailyKm: number, isDataSynced = true): VehicleRecentDay => ({
+  date: '2026-10-12', dailyKm, isDataSynced, sourceProtocol: null, sourceCategory: null,
+});
+
+test('详情合计、平均值和有数据天排除缺失日，保留真实零里程', () => {
+  assert.deepEqual(recentMileageStats([day(100), day(900, false), day(200), day(0)]), {
+    totalKm: 300, synced: 3, avg: 100, max: 200, totalDays: 4,
+  });
+  assert.equal(recentMileageStats([day(0, false)]).synced, 0);
+});
+
+test('列表全区间缺失时显示横杠，即使存在累计里程', () => {
+  const vehicle = { dailyKm: 0, isDataSynced: false, totalKm: 64413.6 } as MonitoringVehicle;
+  assert.equal(monitoringMileageValue(vehicle), '—');
+  assert.equal(monitoringMileageValue({ ...vehicle, isDataSynced: true }), 0);
+  assert.equal(monitoringMileageValue({ ...vehicle, isDataSynced: true, dailyKm: 5417 }), 5417);
+});