Add description to List View

[mtias]

The list view is a very useful component of the block editor but currently lacks guidance. It'd be good to explore some contextual text that can describe what it does, what functionality is possible with it (drag and drop, insert in place, discovery, focused mode, etc).

[pablohoneyhoney]

An attempt to provide context could be:
Manage and reorder blocks and groups of blocks used in your page.
Which could contextually adapt when it is on a template:
Manage and reorder blocks and groups of blocks used in your template.

[pablohoneyhoney]

I could also see no divider:

[mtias]

Resuming this: I think if we offer a shortcut to directly focus on list view (#65603) we can name it in the description here to give better visibility to it.

cc @richtabor