ui: Network Request Refactor

[mrtracy]

The network request API in the Admin UI is not particularly intuitive and is not scaling well. An overview of current issues:

CachedDataReducer API

CachedDataReducer has an unintuitive API for refreshing data: React components that need routinely-refreshed data (e.g. refresh some data every 10 seconds) must dispatch a "refresh" thunk action inside of both componentDidUpdate and componentWillReceiveProps. The intention is that periodically fetched data will only be fetched only if there is a currently rendered component which needs it. However, this strategy is often unclear to new developers, requires a hack to work correctly (requiring the valid flag to be a connected property), is difficult to debug, and is providing confusion in use cases which do not require data to be periodically refreshed.

Additionally, the use of CachedDataReducer as a "reducer factory", while reducing boilerplate, does seem to introduce some conceptual complexity; it is also only one possible solution to re-using the cached data pattern across multiple endpoints. We might investigate the use of type-safe accessors (the pattern currently used for local settings) instead of directly typing the repository.

Project Organization

Currently, the endpoint definitions for our API are under /util/api.ts, while the actual cached data reducers are defined under /redux/apiReducers. Things are basically all over the place; even if we don't change the underlying pattern much, we should reorganize this structure to be more straightforward.

[github-actions]

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