Add newtype wrappers for some low level network primitives

[crocodile-dentist]

We should reconsider the lack of newtype wrappers for things like DNS.Domain, Socket.PortNumber, Socket.SockAddr. If we have them, then:

we are in control of instances (it's not only about orphans, but also about stability);
it's easier to deal with when we'd switch to a different dns / network library.

Ad 1. It becomes a concern because of the ToJSON, and ToCBOR instances - but there's a trap with using instances for version codecs; at some point, one need extra newtype wrappers for new versions of encoding...;

Ad 2. isn't since the libraries we use are pretty stable - but who knows...