优化抢购逻辑：移除手动提前量、冷却累计停止、默认包数2

- 移除用户手动提前量设置，改为固定 100ms 内部提前量
- 新增冷却累计停止：单账号冷却 ≥5 次自动放弃
- 默认发包数从 1 改为 2
- 前端移除提前量输入框和 localStorage 存取

frontend/src/components/console/ControlStrip.vue

@@ -7,12 +7,11 @@ const { scheduleActive, startNow, startSchedule, cancelSchedule, restoreSchedule
 const { reloadAccounts, queryAllScore } = useAccounts()
 
 // 从本地缓存恢复定时设置
-const { savedTime, savedAdv } = restoreSchedule()
+const { savedTime } = restoreSchedule()
 const targetTime = ref(savedTime || '18:00:00')
-const advance = ref(savedAdv)
 
 const handleSchedule = () => {
-  startSchedule(targetTime.value, advance.value)
+  startSchedule(targetTime.value)
 }
 </script>
 
@@ -47,17 +46,6 @@ const handleSchedule = () => {
           step="1"
         >
       </div>
-      <div class="schedule-item">
-        <label>提前</label>
-        <input
-          v-model.number="advance"
-          type="number"
-          min="0"
-          max="5000"
-          step="100"
-        >
-        <span style="color: var(--muted); font-size: 11.5px">ms</span>
-      </div>
     </div>
   </div>
 </template>