DTOs don't work with inheritance

[pboling]

class SortedQueryDto < ::Castkit::DataObject
  optional do
    string :sort
  end
end

class FilteredSortedQueryDto < SortedQueryDto
  optional do
    string :filter
  end
end

FilteredSortedQueryDto.new(sort: "auto")

When you run that you will get:

irb(main):013> FilteredSortedQueryDto.new(sort: "auto")
/var/home/pboling/.local/share/mise/installs/ruby/3.4.3/lib/ruby/gems/3.4.0/gems/castkit-0.3.0/lib/castkit/contract/validator.rb:222:in 'Castkit::Contract::Validator#handle_unknown_keys!': Unknown attribute(s): sort (Castkit::ContractError)

The important bits being the source line: lib/castkit/contract/validator.rb:222 and the error:

'Castkit::Contract::Validator#handle_unknown_keys!':
Unknown attribute(s): sort (Castkit::ContractError)

Am I doing something wrong, or is inheritance not supported?

(This example is contrived, and only for illustration; I don't think it is a good idea to build a sorted filter query like this!)