Summary:
1. only useValue from tree root
2. Pass down props for ui state instead subscribing ad hoc
3. Pass down callbacks, instead of updating atoms ad hoc.
4. Create ui actions object holding api, will use this later on in the vizualizer as some of the same
In general its more verbose but with memoizing perf should be fine should hopefully be easier to reason about components and what they can do as things are more explicit
Hopefully this serves as a general template for how to organise the react code going forward
Reviewed By: lblasa
Differential Revision: D41872490
fbshipit-source-id: 94a33b0e951c04df367ba102fa0a097d4a0389cd
040240ec34