derive Object on tuple structs or allow Type trait impl

[nicrosengren]

This is in regards to poem-openapi.

Description of the feature

Allow implementation of trait Type by exposing MetaSchemaRef and Registry.

or

Make the Object derive macro accept tuple structs and use the inner types implementation of Type.

Background

I commonly use tuple structs to wrap types from dependencies to allow more control over them. This might be to control parsing, easier maintenance or just adding my own functions to them.

In this case it is my type DateTime, which is currently implemented using time::OffsetDateTime (which you support).

In order to use these types with poem-openapi I need to implement the trait Type.
This is however not possible since neither MetaSchemaRef nor Registry are exported by poem-openapi.

Using the Object derive macro with remote is not possible since fields need to be named.

It would be great if the Object derive macro allowed tuple structs and used the Type impl of the wrapped type.