Function spawn_with_runner 

pub fn spawn_with_runner(
    runner: &RunnerConfig,
    command: &str,
    cwd: &Path,
    stdout: File,
    stderr: File,
    extra_env: &HashMap<String, String>,
    pipe_stdin: bool,
    execution_profile: &ResolvedExecutionProfile,
) -> Result<Child>

Spawns a runner process and routes output directly to files.