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

int RPCPort() const { return nRPCPort; }
    CBaseChainParams() = delete;
    CBaseChainParams(const std::string& data_dir, int rpc_port) : nRPCPort(rpc_port), strDataDir(data_dir) {}
private:
    int nRPCPort;
    std::string strDataDir;
};
/**
 * Creates and returns a std::unique_ptr<CBaseChainParams> of the chosen chain.
 * @returns a CBaseChainParams* of the chosen chain.
 * @throws a std::runtime_error if the chain is not supported.
 */
std::unique_ptr<CBaseChainParams> CreateBaseChainParams(const std::string& chain);
/**
 *Set the arguments for chainparams
 */
void SetupChainParamsBaseOptions(ArgsManager& argsman);
/**
 * Return the currently selected parameters. This won't change after app
 * startup, except for unit tests.
 */
const CBaseChainParams& BaseParams();
void SelectBaseParams(const std::string& chain);
#endif