feat: add environment variables and docs

ref: N25B-352

src/robot_interface/endpoints/socket_base.py

@@ -2,6 +2,8 @@ from abc import ABCMeta
 
 import zmq
 
+from robot_interface.core.config import settings
+
 
 class SocketBase(object):
     """
@@ -59,7 +61,7 @@ class SocketBase(object):
         if bind:
             self.socket.bind("tcp://*:{}".format(port))
         else:
-            self.socket.connect("tcp://localhost:{}".format(port))
+            self.socket.connect("tcp://{}:{}".format(settings.agent_settings.control_backend_host, port))
 
     def close(self):
         """Close the ZeroMQ socket."""