FSAnimationStep.validated constructor

FSAnimationStep.validated({ required FSAnimation animation, Duration delay = Duration.zero, })

✅ ADDED: Factory constructor with validation

Implementation

factory FSAnimationStep.validated({
  required FSAnimation animation,
  Duration delay = Duration.zero,
}) {
  assert(delay >= Duration.zero, 'Delay cannot be negative');
  return FSAnimationStep(
    animation: animation,
    delay: delay,
  );
}