feat: setup gesture agent and adjust command port for the UI

ref: N25B-334

src/control_backend/agents/actuation/robot_gesture_agent.py

@@ -0,0 +1,108 @@
+import json
+
+import zmq
+import zmq.asyncio as azmq
+
+from control_backend.agents import BaseAgent
+from control_backend.core.agent_system import InternalMessage
+from control_backend.core.config import settings
+from control_backend.schemas.ri_message import GestureCommand
+
+
+class RobotGestureAgent(BaseAgent):
+    """
+    This agent acts as a bridge between the control backend and the Robot Interface (RI).
+    It receives speech commands from other agents or from the UI,
+    and forwards them to the robot via a ZMQ PUB socket.
+
+    :ivar subsocket: ZMQ SUB socket for receiving external commands (e.g., from UI).
+    :ivar pubsocket: ZMQ PUB socket for sending commands to the Robot Interface.
+    :ivar address: Address to bind/connect the PUB socket.
+    :ivar bind: Whether to bind or connect the PUB socket.
+    :ivar gesture_data: A list of strings for available gestures
+    """
+
+    subsocket: azmq.Socket
+    pubsocket: azmq.Socket
+    address = ""
+    bind = False
+    gesture_data = []
+
+    def __init__(
+        self,
+        name: str,
+        address=settings.zmq_settings.ri_command_address,
+        bind=False,
+        gesture_data=None,
+    ):
+        if gesture_data is None:
+            gesture_data = []
+        super().__init__(name)
+        self.address = address
+        self.bind = bind
+
+    async def setup(self):
+        """
+        Initialize the agent.
+
+        1. Sets up the PUB socket to talk to the robot.
+        2. Sets up the SUB socket to listen for "command" topics (from UI/External).
+        3. Starts the loop for handling ZMQ commands.
+        """
+        self.logger.info("Setting up %s", self.name)
+
+        context = azmq.Context.instance()
+
+        # To the robot
+        self.pubsocket = context.socket(zmq.PUB)
+        if self.bind:  # TODO: Should this ever be the case?
+            self.pubsocket.bind(self.address)
+        else:
+            self.pubsocket.connect(self.address)
+
+        # Receive internal topics regarding commands
+        self.subsocket = context.socket(zmq.SUB)
+        self.subsocket.connect(settings.zmq_settings.internal_sub_address)
+        self.subsocket.setsockopt(zmq.SUBSCRIBE, b"command")
+
+        self.add_behavior(self._zmq_command_loop())
+
+        self.logger.info("Finished setting up %s", self.name)
+
+    async def stop(self):
+        if self.subsocket:
+            self.subsocket.close()
+        if self.pubsocket:
+            self.pubsocket.close()
+        await super().stop()
+
+    async def handle_message(self, msg: InternalMessage):
+        """
+        Handle commands received from other internal Python agents.
+
+        Validates the message as a :class:`GestureCommand` and forwards it to the robot.
+
+        :param msg: The internal message containing the command.
+        """
+        try:
+            speech_command = GestureCommand.model_validate_json(msg.body)
+            await self.pubsocket.send_json(speech_command.model_dump())
+        except Exception:
+            self.logger.exception("Error processing internal message.")
+
+    async def _zmq_command_loop(self):
+        """
+        Loop to handle commands received via ZMQ (e.g., from the UI).
+
+        Listens on the 'command' topic, validates the JSON and forwards it to the robot.
+        """
+        while self._running:
+            try:
+                _, body = await self.subsocket.recv_multipart()
+
+                body = json.loads(body)
+                message = GestureCommand.model_validate(body)
+
+                await self.pubsocket.send_json(message.model_dump())
+            except Exception:
+                self.logger.exception("Error processing ZMQ message.")