List view drag and drop: Make it more obvious blocks can be dragged

[talldan]

What problem does this address?

This was feedback on the PR that enabled drag and drop - #33320 (comment)

What is your proposed solution?

A simple first option might be to show the 'drag' pointer when hovering over the block icon.

There might also be other visual improvements, though a drag handle might make things a bit visually busy.

[jasmussen]

While closed now, there are some mockups for how this could be handled in the original issue #29727 which I've copied here for easier reference:

Note: This change should apply to anywhere we use the List View component. Here shown for the Navigation block:

Make the entire list view item draggable:

You'd still be able to focus the item itself, or the ellipsis, individually:

The ellipsis menu contains a "Move to..." item that duplicates the move action.

[ramonjd]

I played around with this and felt that a modest start would be to change the cursor. The drag cursor is fairly universal.

• List view: add drag cursor to draggable list items #57493

2024-01-03.15.11.34.mp4

Adding the dragHandle cursor clutters the UI a bit in my opinion.

There's also an option of switching the block icon to dragHandle onHover, but it still seems confusing.