Configuration simplification

[BiagioFesta]

This PR aims to simplify (and minimize) wtransport configurations (both server and client).

In particular, it gives the possibility to configure a server and client directly passing the underlying transport configuration (i.e., quinn). This follows the same approach adopted for the underlying TLS stack (i.e. rustls).

Some advanced methods are been removed, such as: token_key and enable_key_log in the spirit of the mission of wtransport: having a minimal and user-friendly API. However, providing (with a single method) the configuration via quinn and rustls all advanced configurations are still possible.

This PR also changes DnsResolver interface: it simplifies the code and avoid usage of a Mutex for DNS resolution

[finnbear]

I successfully ported my app! The main side effect was needing to depend on quinn and quinn-proto, not just the latter.

[BiagioFesta]

wtransport re-export quinn: one can use wtransport::quinn:....

What about re-exporting quinn-proto as well?

[finnbear]

wtransport re-export quinn: one can use wtransport::quinn:....

Cool, I missed that!

What about re-exporting quinn-proto as well?

Yes, please! (unless quinn could be convinced to have quinn::proto, allowing wtransport::quinn::proto 👀) Edit: no longer necessary!

[BiagioFesta]

What is missing in quinn you'd consider for rexport? I see HandshakeTokenKey is already re-exported (as others)

[finnbear]

Still working for me! (you can revert re-exporting quinn-proto)

[BiagioFesta]

Still working for me! (you can revert re-exporting quinn-proto)

Thank you for reviewing this and feedback.

Feel free to join the discord server so I can ping you some other time, for other reviews :P

[finnbear]

Feel free to join the discord server so I can ping you some other time, for other reviews :P

Amazing; didn't know that existed!