Improve camera status and production startup

agv_app/utils/arm_client.py

@@ -51,6 +51,10 @@ class ArmClient:
             self._sock.close()
             self._sock = None
 
+    def is_connected(self) -> bool:
+        """返回当前 TCP 连接是否仍由客户端持有。"""
+        return self._sock is not None
+
     def reconnect(self) -> bool:
         self.close()
         time.sleep(1)
@@ -167,4 +171,4 @@ class ArmClient:
         return self
 
     def __exit__(self, *args):
-        self.close()
+        self.close()