Propagate status and statusText from fetchInternal()

[petebacondarwin]

See #287 (comment)

[kination]

@petebacondarwin seems it is already sending error with status/statusText

throw new Error(
      `Failed to fetch ${resource} - ${response.status}: ${response.statusText}\nInvalid JSON response:\n${jsonText}`
    );

is there something more for this issue?

[petebacondarwin]

The idea is that rather than throwing a generic error here, we return an object that contains the status information, so that the caller can then choose what to do (and perhaps throw an error if appropriate).

[threepointone]

Based on the last few months, looks like the .code has been useful and is usually a more refined form of .status. When we don't have a .code, we throw the error with the .status and .statusText in the message, which has been sufficient. I think we may not need to do anything else here, so do you suppose we should close this out, and open a fresh issue when we have a specific need?