expandShortcut method
Expands the client-side l shortcut: a line whose first word is l
becomes listCommand with the rest of the line as its arguments. Any
other line is returned unchanged.
Implementation
String expandShortcut(String line) {
final match = _listShortcut.firstMatch(line);
if (match == null) return line;
return listCommand(match.group(1)?.trim() ?? '');
}