Ivan Meredith, That's where we're hoping to get. But testing notes are getting included as part of new/unstarted as well as user-opened issues. In fact, I'd like to start participating in the issue planning process earlier, so that we can do just what you've described - ensure that there are tests included in the initial PRs. We're getting there, it's just not a quick process. There was a lot of catching up to do first.
I haven't been applying testing notes to the stories mostly because stories tend to be broader in scope, and include >1 issue (task/bug/rfe/etc) in them.