* Set up markdown rendering, update theme.
* Improve focus and handle expanding for markdown cells
* Add keybindings for expanding/navigating cells
* Improve editor autofocus when navigating with shortcuts
* Add tests
* Render markdown on the client
* Don't render cell initial data and make a request instead
* Sync session data within LV client
* Add basic session UI
* Add operations for setting notebook and section name
* Update notebook and section name from the UI
* Some cleanup
* Return current data upon client registartion to avoid race conditions
* Small fixes
