Add support for `attributes_for_inspect`

[makmic]

ActiveRecord let's you define which attributes are part of #inspect by defining attributes_for_inspect on the model (Reference). ActiveType::Object does not currently support that - I would suggest to add this behavior as it has a low cost and clear (but also small) benefit.

WDYT? I can help out with the implementation if you want me to.

[kratob]

Hi @makmic. If this can be implemented without a multitude of version switches or the like, we would happily merge a PR for this.

[makmic]

👍

Here is the corresponding PR: #215

I tried to stay close to the rails implementation: https://github.com/rails/rails/blob/main/activerecord/lib/active_record/core.rb#L118

[kratob]

@makmic Thanks!

Released as 2.8.0.