Zoom Out: Hold to drag and drop nested patterns.

[scruffian]

What problem does this address?

Following on from #63862, we want to prioritise patterns as sectioning elements, but we also don't want to totally prevent nested patterns.

What is your proposed solution?

When in zoom out mode, and using drag and drop, if a user holds a pattern over another pattern for X milliseconds, they become able to nest the pattern inside another pattern.

This needs to be done after #63862

[MaggieCabrera]

Do we need to do this if we said we weren't going to allow drag and drop inside patterns?

[scruffian]

I think it would be a nice improvement to be able to do it after you hold for X seconds, but probably low priority.

[richtabor]

Perhaps in the future we can re-explore this, but currently I think it's fine that you can disengage zoom out now, to add patterns wherever you'd like. And with #65945, it may be confusing determining the state of editing with this extra hold to drag and drop patterns within UX.