Make it clearer why workspaces sometimes don't appear on the prioritization screen

We limit visible unprioritized features on this screen to 100. If the first workspace visible has more than that, subsequent workspaces don't show.

This is working as intended but can be confusing because it's not obvious why the other workspaces aren't visible.

Show a message on the screen in this case along the lines of "some workspaces are hidden because only 100 features can show at a time."