Unable to connect until next restart after bad handshake

[Quantumplation]

If you attempt to connect via the dolos socket with an incorrect network magic, you will get an HandshakeProtocol(Plexer(AgentDequeue)) error.

However, even after correcting the network magic, subsequent connections will fail with connection refused:

ConnectFailure(Os { code: 61, kind: ConnectionRefused, message: "Connection refused" })

[Quantumplation]

Note that, much like #293, the only indication that something is wrong comes when you shut down the node

2024-07-13T20:46:59.257467Z  INFO stage{stage="ledger"}: gasket::runtime: switching stage phase prev_phase=Teardown next_phase=Ended
Error:   × serve thread
  ├─▶ serving Ouroboros
  ╰─▶ server error: handshake version not accepted

[scarmuega]

fixed by #297