fix: 拒绝保存未来日期的记录(防止改手机时间污染数据)

用户改手机时间到未来,record.date 就会变成未来时间,
推上云后污染排行榜统计。saveRecord 增加 1 分钟宽容度的
未来时间校验,触发时 toast 提示 + 静默拒绝保存。

utils/storage.js

@@ -49,6 +49,18 @@ const getRecords = () => {
 
 const saveRecord = (record) => {
   record.id = String(Date.now()) + '_' + (++_idSeq)
+
+  // Defensive: reject records with a future date. Indicates the user has
+  // changed their phone clock, which would otherwise poison the cloud
+  // leaderboard (and their own stats) with impossible timestamps. Allow
+  // a 1-minute tolerance for normal clock skew.
+  const recordTime = new Date(record.date.replace(/-/g, '/')).getTime()
+  if (recordTime > Date.now() + 60 * 1000) {
+    console.warn('[storage] saveRecord rejected: future date', record.date)
+    wx.showToast({ title: '系统时间异常,请检查', icon: 'none' })
+    return
+  }
+
   const records = getRecords()
   const month = record.date.substring(0, 7)
   if (!records[month]) records[month] = []