Consistent API for request functions

[jhpedemonte]

Description

We currently have an inconsistent way for handling errors for our public APIs. For example:

• performSearch (which uses useDataApi) works in conjunction with searchResponseStore to make available the loading and error states. If a request returns an error, searchResponseStore.isError is set to true.
• fetchAggregations throws an error on a request error

We should be consistent across our APIs -- probably need to make use of useDataApi across the board.

NOTE: This would be a breaking change, since it would change the API.

Tasks

• Architect for consistent loading/error/cancellation handling across all of the public APIs.
• Implement changes
• Update docs
• Update tests

Acceptance Criteria

• Deb can use the public APIs and handle errors in a consistent manner.