Add component level documentation

Not super high priority (and I can start contributing once the mvp features are better) but right now the wiki documentation is really high level and I spend a lot of time poking around all over the code figuring out how things work. I'm thinking something like [styleguidist](https://github.com/styleguidist/react-styleguidist) might be a good start.

https://blog.bitsrc.io/6-tools-for-documenting-your-react-components-like-a-pro-5027cdfb40c6

Start by reviewing the existing wiki documentation and the React frontend's component structure, then read the linked Styleguidist project and reference article. Define which components need documentation and how it should be maintained. Done means contributors can understand component behavior without searching throughout the code.

Written by the indexing model from the issue text.