Tidy up sidebar + use screen metadata (#6424)
* Use DevTools screens directly
* Switch to using ScreenMetaData
* Fix typos
* Switch to using MenuItemButton
This closes the menu correctly when items are clicked
* Detect whether debug sessions are web
* Tweak colours and add icons
* Hide VM Tools + put Deep Links behind flag
* Review tweaks
* Switch _shouldIncludeScreen to a switch expression
+ add a TODO
