Function resolve_session_root_for_cli 

pub fn resolve_session_root_for_cli(
    flag: Option<&Path>,
    repo_cfg_override: Option<&Path>,
    global_cfg_path: &Path,
    cwd: &Path,
) -> Result<PathBuf>

Same cascade as resolve_session_root, but suitable for read-only session commands (ls, logs, discard) that may run outside any repo. Skips the validation+merge that Config::load performs (we only need the session-root key) and degrades silently when the repo or global config file is missing – the user might have neither and just want the XDG default.