[ESPmDNS] MDNSResponder does not have methods to receive TXT record keys (only values).

[filimonic]

[ESPmDNS] MDNSResponder does not have methods to receive TXT record keys (only values).

MDNSResponder should have a String MDNSResponder::key(int idx, int txtIdx) identical to String MDNSResponder::txt(int idx, int txtIdx) but for keys

String MDNSResponder::key(int idx, int txtIdx) {
    mdns_result_t * result = _getResult(idx);
    if(!result){
        log_e("Result %d not found", idx);
        return "";
    }
    if (txtIdx >= result->txt_count) return "";
    return result->txt[txtIdx].key;
}