passes method
Validates the value using the given context.
Returns true if valid, otherwise false.
Implementation
@override
FutureOr<bool> passes(ValidationContext context) {
final args = context.parameters;
final data = context.data;
if (args.isEmpty) return false;
final otherField = args[0];
final otherValue = data[otherField]; // null if missing
final value = context.value;
return value == otherValue;
}