Channel types in annotations

[Bluenix2]

Summary

This issue is opened to request help and ideas for how to support Discord's new channel_types field on Application command options.

Description

The problem isn't implementing channel_types - that is rather trivial with how the library has been structured - it's how to support it in a good API.

The easiest way is to add a keyword argument to the Option default and decorator that accepts an enum but if possible I would like to explore a way to use annotations.

[Bluenix2]

This is no longer such a big problem since wumpy-models has been fleshed out, there now exists channel classes that can be used. wumpy-interactions should detect a Union of these to specify the channel types using Option.determine_union(). PR is welcome!