Publication blocknode design

Things to keep in mind:

heading children does not have a visual indentation, only the left line
markers are optional

Blocknode states

1.
hover
embeds have also controls ythat depend on the embed type:
publication/block
expand/collapse
open in a new window
version exact/latest
turn into block/document
account
open in new window
view type: content/card
group
open in new window
view: content/card
comment
open in new window
2.
highlighted
when the blockref is present in the URL (current yellow)
3.
embed
it shoudl show the side annotation of the source document
4.
collapsed
5.
expanded