[SERIAL] Enable SERIAL to X communication (#2068)

Add Serial as a communication layer so as to transmit data to/from serial
Enable discovery of BT sensors through serial
Add serial heartbeat

Change discovery principle for interval and intervalacts, keep them always discovered and deactivate adaptivescan when changed. Instead of removing their discovery when adaptive scan is activated

Increase JSON_MSG_BUFFER_MAX as we are now using const char* and it requires more memory for Arduino Json Deserialization

Co-authored-by: Florian <1technophile@users.noreply.github.com>

main/ZdisplaySSD1306.ino

@@ -152,7 +152,7 @@ Handler for mqtt commands sent to the module
 - log-oled: boolean
   Enable / Disable display of log messages on display
 */
-void MQTTtoSSD1306(char* topicOri, JsonObject& SSD1306data) { // json object decoding
+void XtoSSD1306(const char* topicOri, JsonObject& SSD1306data) { // json object decoding
   bool success = false;
   if (cmpToMainTopic(topicOri, subjectMQTTtoSSD1306set)) {
     Log.trace(F("MQTTtoSSD1306 json set" CR));
@@ -222,7 +222,7 @@ void MQTTtoSSD1306(char* topicOri, JsonObject& SSD1306data) { // json object dec
     if (success) {
       stateSSD1306Display();
     } else {
-      Log.error(F("[ SSD1306 ] MQTTtoSSD1306 Fail json" CR), SSD1306data);
+      Log.error(F("[ SSD1306 ] XtoSSD1306 Fail json" CR), SSD1306data);
     }
   }
 }