fix: scheduler shutdown (eosphoros-ai#1237)

dbgpt/app/initialization/scheduler.py

@@ -24,17 +24,22 @@ def __init__(
         self.system_app = system_app
         self._scheduler_interval_ms = scheduler_interval_ms
         self._scheduler_delay_ms = scheduler_delay_ms
+        self._stop_event = threading.Event()
 
     def init_app(self, system_app: SystemApp):
         self.system_app = system_app
 
     def after_start(self):
         thread = threading.Thread(target=self._scheduler)
         thread.start()
+        self._stop_event.clear()
+
+    def before_stop(self):
+        self._stop_event.set()
 
     def _scheduler(self):
         time.sleep(self._scheduler_delay_ms / 1000)
-        while True:
+        while not self._stop_event.is_set():
             try:
                 schedule.run_pending()
             except Exception as e: