Found it. It's in a postgresql table called Apps in field named Description. Intuitive! What's really great from an audit perspective, is that it stores all of the history. Even after an app has been deleted. We'll be entering our change request numbers in the description field before publishing to a stream. That way when the auditors come in 1 year from now and want to see the corresponding change request for every promotion, all we have to do is run a report on the apps table. Nice!