feat: added pause functionality

ref: N25B-350

src/control_backend/schemas/ri_message.py

@@ -64,3 +64,14 @@ class GestureCommand(RIMessage):
         if self.endpoint not in allowed:
             raise ValueError("endpoint must be GESTURE_SINGLE or GESTURE_TAG")
         return self
+
+class PauseCommand(RIMessage):
+    """
+    A specific command to pause or unpause the robot's actions.
+
+    :ivar endpoint: Fixed to ``RIEndpoint.PAUSE``.
+    :ivar data: A boolean indicating whether to pause (True) or unpause (False).
+    """
+
+    endpoint: RIEndpoint = RIEndpoint(RIEndpoint.PAUSE)
+    data: bool