Implement private network secured via a pre-shared key using libp2p [pnet](https://github.com/libp2p/rust-libp2p/tree/master/transports/pnet]. When in "private net" mode a node will only accept connections with peers after verifying they know the same pre-shared key. pnet itself is a transport through which a connection is (in libp2p terms) "upgraded".
It is only possible to run a private net when using TLC as the base transport (QUIC not supported) and so if a pre-shared key is provided the node is forced into using TLC regardless of other configurations.
[x] introduce pnet network behaviour
[x] accept pre-shared key in configuration file and via cli
[x] force TLC when pre-shared key provided
[x] log warnings if QUIC transport was requested
[ ] network tests: i tried to write some simple network tests but it doesn't seem possible without introducing a new swarm just for testing, I believe "memory" multiaddr would need to be supported in our core P2pandaBehaviour. This would require some additional exploration and as we're using pnet in it's basic setup (which is tested on the libp2p side) it seems ok to me that there are no tests in this place
📋 Checklist
[x] ~Add tests that cover your changes~ (see above)
[x] Add this PR to the Unreleased section in CHANGELOG.md
Implement private network secured via a pre-shared key using libp2p [pnet](https://github.com/libp2p/rust-libp2p/tree/master/transports/pnet]. When in "private net" mode a node will only accept connections with peers after verifying they know the same pre-shared key.
pnetitself is a transport through which a connection is (in libp2p terms) "upgraded".It is only possible to run a private net when using TLC as the base transport (QUIC not supported) and so if a pre-shared key is provided the node is forced into using TLC regardless of other configurations.
pnetnetwork behaviourP2pandaBehaviour. This would require some additional exploration and as we're using pnet in it's basic setup (which is tested on the libp2p side) it seems ok to me that there are no tests in this place📋 Checklist
CHANGELOG.md