Function session_is_reachable 

pub fn session_is_reachable(
    config_dir: &str,
    working_dir: &str,
    sid: &str,
) -> bool

Would --resume <sid> find its conversation under this exact CLAUDE_CONFIG_DIR? This is the whole of what the CLI checks before answering “No conversation found with session ID” — so asking it up front predicts a resume’s success without spawning anything.