Fix systemd misjudging by sending heartbeats.

main.rb

@@ -24,6 +24,7 @@ end
 
 require_relative 'method_executor' # 日志系统在此时初始化
 require_relative 'server_status_detector'
+require_relative 'systemd_notifier' # 心跳系统在此时初始化
 
 MethodExecutor.record("info", "mainloop", "MineSentinel started, entering mainloop.")
 
@@ -58,9 +59,13 @@ def main
         MethodExecutor.record("info", "mainloop", "Action: ForceResetServerProcess triggered.")
         MethodExecutor.reset_minecraft_server
         # 重启后等待服务器启动（MC服务器启动通常需要30秒~2分钟）
-        cooldown = 200 # 200秒冷却期
+        cooldown_duration = 200 # 200秒冷却期
+        cooldown_beg = Time.now
         MethodExecutor.record("info", "mainloop", "Cooling down #{cooldown}s for server startup...")
-        sleep cooldown
+        while Time.now < cooldown_beg + cooldown_duration
+          sleep 1
+          SystemdNotifier.notify("WATCHDOG=1")
+        end
         MethodExecutor.record("info", "mainloop", "Cooldown finished, resuming monitoring.")
       end
     end
@@ -70,5 +75,6 @@ end
 
 while true
   sleep 1.5
+  SystemdNotifier.notify("WATCHDOG=1")
   main
 end