[Unsupported] Dashboard Userscript: Leech, Apprentice, and Guru detail (aka SRS level progress)

I moved the [Unsupported] text to the front (for this topic only) so it doesn’t get missed when the title gets cropped.

I reimplemented hitechbunny’s leech formula into my Additional Filters script easily enough a couple months ago. Maybe I can leverage that and the UI code from this script to make a new version. I can at least look into it when I have time over the next few weeks.