isAfterOrSameAs method
Returns true if this date is after or same as the given date.
Example:
final date1 = DateTime(2024, 2, 25);
final date2 = DateTime(2024, 2, 24);
final isAfter = date1.isAfterOrSameAs(date2);
// returns: true
Implementation
bool isAfterOrSameAs(DateTime date) => difference(date).inSeconds >= 0;