Add a field formatter to render user-visible order links (instead of admin-only canonical route)

Wasn't really sure what to call it, but here's a start. Working fine in production on the site where I needed this.

phpunit (next minor) is failing, but that seems to be about new 11.2.x deprecations, so I don't think that's anything I need to worry about here. Everything else is now green.

I'm fine with this change, committed, thank you!