formatDate function
Implementation
String formatDate(DateTime? date) {
if (date == null) return 'Unknown';
final now = DateTime.now().toLocal();
final diff = now.difference(date).inDays;
if (diff == 0) return 'Today';
if (diff == 1) return 'Yesterday';
if (diff < 7) return DateFormat('EEE').format(date);
return date.year == now.year
? DateFormat('MMM dd').format(date)
: DateFormat('MM/dd/yy').format(date);
}