To be able to label incoming tor connections as different from normal localhost connections in e.g. `getpeerinfo` and the peers list in the GUI it'd be useful to have them connect on an alternative local-only port. Or even better, a UNIX socket.

For manually set-up hidden services this would have to be configured manually and could add a `hsport` option or such. The external port would still appear as `XXXXXXXXX.onion:8333`, however internally it would redirect to a that port.

In the case of `torcontrol` this would be easy to set up automatically. It could add a new (localhost) binding port automatically and this code would have to be changed:
- https://github.com/bitcoin/bitcoin/blob/master/src/torcontrol.cpp#L441
- https://github.com/bitcoin/bitcoin/blob/master/src/torcontrol.cpp#L477

{
    
    unsigned int nRemaining = CMessageHeader::HEADER_SIZE - nHdrPos;
    unsigned int nCopy = std::min(nRemaining, nBytes);
    memcpy(&hdrbuf[nHdrPos], pch, nCopy);
    nHdrPos += nCopy;
    
    if (nHdrPos < CMessageHeader::HEADER_SIZE)
        return nCopy;
    
    try {
        hdrbuf >> hdr;
    }
    catch (const std::exception&) {
        LogPrint(BCLog::NET, "HEADER ERROR - UNABLE TO DESERIALIZE, peer=%d\n", m_node_id);
        return -1;
    }
    
    if (memcmp(hdr.pchMessageStart, m_chain_params.MessageStart(), CMessageHeader::MESSAGE_START_SIZE) != 0) {
        LogPrint(BCLog::NET, "HEADER ERROR - MESSAGESTART (%s, %u bytes), received %s, peer=%d\n", hdr.GetCommand(), hdr.nMessageSize, HexStr(hdr.pchMessageStart), m_node_id);
        return -1;
    }