Calendar constructor
      
      Calendar(
    
    
- DateTime dateTime
Implementation
Calendar(DateTime dateTime)
    : calendarDate = dateTime.subtract(Duration(days: dateTime.day - 1)) {
  for (final day in dayLabels) {
    insertColumn(header: day, alignment: TextAlignment.right);
  }
  // ISO format has 1..7 for Mon..Sun, so we adjust this to match the array
  final startDate = calendarDate.weekday == 7 ? 0 : calendarDate.weekday;
  final todayColor = ConsoleColor.brightYellow.ansiSetForegroundColorSequence;
  final calendarDates = <String>[
    for (int i = 0; i < startDate; i++) '',
    for (int i = 1; i <= 31; i++)
      if (calendarDate.add(Duration(days: i - 1)).month == calendarDate.month)
        if (calendarDate.year == DateTime.now().year &&
            calendarDate.month == DateTime.now().month &&
            i == DateTime.now().day)
          '$todayColor$i$ansiResetColor'
        else
          '$i',
  ];
  while (true) {
    insertRow(calendarDates.take(7).toList());
    if (calendarDates.length > 7) {
      calendarDates.removeRange(0, 7);
    } else {
      break;
    }
  }
  title = DateFormat('MMMM yyyy').format(calendarDate);
}