Enable all features in for published Rust Docs of protocols crates

[plebhash]

Currently, the public Rust Docs for protocols crates are rendered without enabling any of the feature flags available on the crates.

That prevents many important elements from being displayed (e.g.: State in codec_sv2, which depends on the noise_sv2 feature flag being enabled).

In order to change that, we need to add the following to their Cargo.toml:

[package.metadata.docs.rs]
all-features = true

ref: https://docs.rs/about/metadata