> net: update incorrect Doxygen documentation in netbase.cpp
> net: move Doxygen docs from netbase.cpp to netbase.h
This is a backport of [[https://github.com/bitcoin/bitcoin/pull/21444 | core#21444]]
Notes :
- the third commit is not applicable due to D11042 (replacement of `SOCKET &hSocketRet` with `Sock &sock` in the function signature).
- the doxygen doc for `Socks5` cannot be moved because we didn't backport core#19203, so it is still a static function not defined in the header.
Depends on D11067