feat: hot reload for config/templates and GitPython-based hot update with pre-update notification

alerter.py

@@ -26,6 +26,19 @@ class Alerter:
         self._last_alert_ts = 0.0
         self._task = None
 
+    def apply_config(self, cfg: dict):
+        """热重载告警参数（保留告警状态）。"""
+        self.interval = cfg.get("interval", self.interval)
+        new_threshold = cfg.get("cpu_threshold", self.threshold)
+        if new_threshold != self.threshold:
+            log.info("告警阈值变更: %.0f%% -> %.0f%%", self.threshold, new_threshold)
+            self.threshold = new_threshold
+        self.consecutive_need = cfg.get("consecutive", self.consecutive_need)
+        self.cooldown = cfg.get("cooldown", self.cooldown)
+        self.top_n = cfg.get("top_n", self.top_n)
+        self.groups = cfg.get("groups", self.groups) or []
+        self.friends = cfg.get("friends", self.friends) or []
+
     def start(self):
         self._task = asyncio.get_running_loop().create_task(self._loop())