Recently a few issues have come up related to internal change stream stages like DocumentSourceChangeStreamEnsureResumeTokenPresent.

My understanding is that users typically use the $changeStream which is then expanded internally to various internal stages. We should probably just put a single top-level $changeStream node into query stats, but not serialize any of the internal stages. This would both solve existing issues and might make query stats easier to work with, since internal change stream details would not be exposed.