When git users misconfigure their sudoers file, they get an HTTP 500 error which can only be surfaced by using GIT_CURL_VERBOSE.
This is somewhat difficult to detect, and difficult to report.
Detection is difficult because we must distinguish between `sudo` failure and `git-http-backend` failure. This is hard to do from the command results, except by text matching stderr for "sudo".
It's not immediately clear how to run a trivial succeeding command via `git-http-backend` either, as it doesn't have `--help` or `--version` flags that I can find. If we could find such a flag, we could run it after all errors and use it to distinguish between sudo errors and other kinds of error. We could possibly write a trivial, valid request, but this seems like it may be involved.
Even assuming we can detect the error, we're limited in our ability to report it. I wasn't able to find any way to write directly to the console under `git` over HTTP. It's possible some method exists; I didn't dig extremely deeply. Other thoughts are that we could surface an unusual HTTP error code, or preemptively detect this in the repository interface.