feat(model): Introduce poro model plugin

[okuramasafumi]

I found that in a Rails app, we see the following error with serializers for POROs.

NoMethodError: undefined method `columns_hash' for class GoalSettingCourse (NoMethodError)

        @columns_hash = model_class&.columns_hash || {}
                                   ^^^^^^^^^^^^^^

This should be fixed by using Poro model plugin for those serializers.

[skryukov]

Hey, @okuramasafumi thanks for the PR!

I have a question: why do you set typelize_from for a PORO? i.e. commenting out both typelize_from and typelizer_config from the PoroSerializer will end up with the same result 👀

[okuramasafumi]

@skryukov In our Rails app, without typelize_from it automatically sets model and causes the error. However, in the test app, it's under Alba module so typelize_from was required to reproduce the issue. Or maybe I'm wrong, but I couldn't reproduce it without it.