Ros2 Architecture / Best place for LED status?

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I am working on a rover with 3 status LEDS for Rover is powered ( Green LED ) , ROS is running ( Blue LED ), and proximity alert ( Red ). I want to store 3 boolean values in one place where they can be updated by a service or update by subscribed topic, and I will plug in some Python code to manipulate some GPIO pins for the physical LEDs, but I am not sure what kind of Node to put the values in. I expect a service for sonar to publish something when something is too close. I am guessing a subscriber will control the physical LED, but should the values be stored in a Publisher that can connect to a service or Listen for a Topic?