Interactive transition documentation

I don't know if it's the broken documentation, or what, but I can't seem to make Hero work interactively. Does it still work that way?

I was able to find the blog post that is currently a broken link in the documentation in the internet archive here: https://web.archive.org/web/20200415004138/http://lkzhao.com/2017/02/05/hero-interactive-transition.html

Unfortunately, that didn't really help, although it was useful context to have.

I am unclear how Hero works with (or whether it can work with) the `UINavigationController`'s `interactivePopGestureRecognizer` property, but I was able to create a new `UIScreenEdgePanGestureRecognizer` that happens at the same time, and cancel the pop-gesture recognizer when its triggered and I want to use a `Hero` transition instead. The problem is that, once I've started the `Hero` transition using `Hero.shared.start()`, my recognizer's `.changed` case is never called.

I haven't tried reproducing this issue in a simpler stand-alone project, so I don't really know if this is all somehow specific to my codebase, and it very well could be.