fix(api): 修正看板和历史统计口径

src/domain/battery.test.ts

@@ -56,6 +56,20 @@ describe('battery domain', () => {
     expect(response.items[0]?.createTime).toBe('2026-05-10T23:00:00.000Z')
   })
 
+  test('keeps explicit window summaries for limited history slices', () => {
+    const now = new Date('2026-05-11T00:00:00.000Z')
+    const items = rows.map(toBatteryInfo)
+    const response = createBatteriesResponse(items, now, {
+      total: items.length,
+      lowPower: 1,
+      charging: 1,
+    })
+
+    expect(response.total).toBe(2)
+    expect(response.lowPower).toBe(1)
+    expect(response.charging).toBe(1)
+  })
+
   test('creates dashboard aggregate shape without using power as fake SOH', () => {
     const now = new Date('2026-05-11T00:00:00.000Z')
     const snapshot = createDashboardSnapshot(rows.map(toBatteryInfo), now)