Navigation block: Rearranging items

[sarahmonster]

This is intended to splinter conversation from #13690 and allow us to focus the conversation on one part of the problem at a time. We'll loop back to the tracking issue when we've determined a path forward. For this issue, we're focussing on ordering, hierarchy, and sub-menus:

How do I rearrange the items in my menu?

This will probably hinge quite a bit on the direction chosen in #13789 and also on #13791. It's going to be a doozy so we're saving it for last!

[oandregal]

One of the tasks for phase 2 is adding Drag and Drop reordering to the Gallery block. There may be a common mechanism to do both (this and the gallery), as the mechanics seem similar. Cross-posting here for reference and visibility #743

[jwold]

Agreed @sarahmonster that this probably makes sense to tackle after the other issues.

[sarahmonster]

Since design explorations have largely concluded here, I'm closing this ticket as non-actionable, and we can loop back to #13690 or new issues for any further conversation that comes up as development work progresses.

Thanks everyone for all the feedback! 🙌