feat(core): harden sessions settlement and credit activity

bootstrap/app.php

@@ -267,10 +267,14 @@ return Application::configure(basePath: dirname(__DIR__))
         $withSingleServerLock($schedule->command('settlement:mark-overdue-bills --days=7')
             ->dailyAt('02:00')
             ->withoutOverlapping());
-        /** @see docs/01-界面文档.md §2.1 `draw.countdown` */
+        /**
+         * @see docs/01-界面文档.md §2.1 `draw.countdown`
+         * 前端按服务器时间每秒本地计时；后端每 5 秒校准快照和期号边界，
+         * 避免每秒重复启动完整 Artisan 进程。
+         */
         if (config('lottery.realtime_hall_countdown', true)) {
             $withSingleServerLock($schedule->command('lottery:hall-countdown')
-                ->everySecond()
+                ->everyFiveSeconds()
                 ->withoutOverlapping(expiresAt: 5));
         }
     })