API Errors and better response handling in general

[joshua-dean]

Launching an app in S3 mode (such as for the demo) fails unless a .env file is present, which requires terraform to be deployed. #22 is dealing with the AWS configuration specifically, however this and other errors could be more verbosely handled in general.

For example, adding a catch to hit_terraform_api that returns {"data":[]} on a 404 allows the app to launch, rather than a blank screen with a non-descriptive console error.
All frontend-backend interactions should have contingencies for various error codes that include a visual reflection of what went wrong, especially for everything in the demo.