ESPmDNS: Add method for querying discovered service name (#10819)

* Add method for querying service name

* Added implementation for getting service name

* Update mDNS-SD_Extended example to include service name

* ci(pre-commit): Apply automatic fixes

---------

Co-authored-by: pre-commit-ci-lite[bot] <117423508+pre-commit-ci-lite[bot]@users.noreply.github.com>

Author: stefan-sherwood

libraries/ESPmDNS/examples/mDNS-SD_Extended/mDNS-SD_Extended.ino

@@ -68,6 +68,8 @@ void browseService(const char *service, const char *proto) {
       Serial.print("  ");
       Serial.print(i + 1);
       Serial.print(": ");
+      Serial.print(MDNS.instanceName(i));
+      Serial.print(" - ");
       Serial.print(MDNS.hostname(i));
       Serial.print(" (");
       Serial.print(MDNS.address(i));

libraries/ESPmDNS/src/ESPmDNS.cpp

@@ -299,6 +299,15 @@ String MDNSResponder::hostname(int idx) {
   return String(result->hostname);
 }
 
+String MDNSResponder::instanceName(int idx) {
+  mdns_result_t *result = _getResult(idx);
+  if (!result) {
+    log_e("Result %d not found", idx);
+    return String();
+  }
+  return String(result->instance_name);
+}
+
 IPAddress MDNSResponder::address(int idx) {
   mdns_result_t *result = _getResult(idx);
   if (!result) {

libraries/ESPmDNS/src/ESPmDNS.h

@@ -110,6 +110,7 @@ class MDNSResponder {
   }
 
   String hostname(int idx);
+  String instanceName(int idx);
   IPAddress address(int idx);
   IPAddress addressV6(int idx);
   uint16_t port(int idx);