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

src/modules/mileage/mileage-display.ts

@@ -0,0 +1,24 @@
+import type { MonitoringVehicle } from './types';
+import type { VehicleRecentDay } from './api';
+
+export function monitoringMileageValue(vehicle: MonitoringVehicle): number | string {
+  if (vehicle.mileageAnomaly) return '数据异常';
+  if (!vehicle.isDataSynced) return '—';
+  return Math.max(0, vehicle.dailyKm || 0);
+}
+
+export function hasDailyMileage(day: VehicleRecentDay): boolean {
+  return day.isDataSynced && Number.isFinite(day.dailyKm) && day.dailyKm >= 0;
+}
+
+export function recentMileageStats(days: VehicleRecentDay[]) {
+  const validDays = days.filter(hasDailyMileage);
+  const totalKm = validDays.reduce((sum, day) => sum + day.dailyKm, 0);
+  return {
+    totalKm,
+    synced: validDays.length,
+    avg: validDays.length ? totalKm / validDays.length : 0,
+    max: Math.max(1, ...validDays.map(day => day.dailyKm)),
+    totalDays: days.length,
+  };
+}