Support passing `SIGINT` to scripts that are running via `devbox run` about devbox

[kadaan]

It does seem to be working some of the time. I've yet to determine why is it not working all the time. Some scripts correctly respond to SIGINT when run but they don't when run via devbox run.

[kadaan]

This seems similar to the issues that this PR fixed in dagger: dagger/dagger#5712

Their change is essentially doing the following to nix/run.go:

cmd := exec.CommandContext(ctx, shPath, "-c", cmdWithArgs)
	cmd.Env = envPairs
	cmd.Dir = projectDir
	cmd.Stdin = os.Stdin
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stderr
	cmd.Cancel = func() error {
		return syscall.Kill(cmd.Process.Pid, syscall.SIGTERM)
	}

With my limited testing, this seems to fix the issue.

[gcurtis]

Thanks for the submitting a PR with your fix. I'd still like to understand a bit more why this is happening. Could you provide a few more details?

• What's the exact script that's not responding to SIGINT?
• What shell are you using (for running devbox and the script)?
• Are you sending SIGINT by pressing ctrl-c in the shell? Or are you signaling the devbox process directly?
• Is this happening on macOS or Linux?

When I try to repro using this config:

{
  "shell": {
    "scripts": {
      "zzz": "/bin/sleep 5"
    }
  }
}

and run devbox run zzz followed by ctrl-c, the sleep process exits. This is what I'd expect because the shell should be signaling the entire process group.