How to use the new "complete" feature internally?

@knolleary You may have seen my post here. I am working with pm2, and very keen to perform graceful shutdowns.

If there is still time for NR to adopt it internally, I would like to explore the idea of managing it with pm2. What events/methods are available to the runtime currently to know if a flow is running or not? Perhaps, I am asking the wrong ques, so happy to be guided.