Issue #3558330: Handle Client Exceptions

It seemed to make the most sense to treat a client exception as a failure, like when there is no $response, instead of leaving it as processing as is what happens with a 429 response. In needing to initialize the state, I chose Processing as it made more sense than Success or Failure, that being said, there is no code path out of the logic where it is not going to be either success or failure.

Closes #3558330