message: netinfo: add ConnectionTypeForNetinfo member helper function
diff: @@ -351,6 +351,14 @@ private:
  const double milliseconds{round(1000 * seconds)};
  return milliseconds > 999999 ? "-" : ToString(milliseconds);
  }
  + std::string ConnectionTypeForNetinfo(const std::string& conn_type) const
  + {
  + if (conn_type == "outbound-full-relay") return "full";
  + if (conn_type == "block-relay-only") return "block";
  + if (conn_type == "manual" || conn_type == "feeler") return conn_type;
  + if (conn_type == "addr-fetch") return "addr";
  + return "";
  + }
  const UniValue NetinfoHelp()
  {
  return std::string{
  