void setup() {
Serial.begin(115200);
Serial.println("Starting MQTT Broker (Simulated)...");
delay(1000);
Serial.println("Subscriber connected to topic: test/topic");
delay(1000);
}
void loop() {
  
String message = "Hello, MQTT!";
Serial.println("Published: " + message);
delay(1000);
// Simulate Subscriber receiving same message
Serial.println("Received message: " + message + " on topic: test/topic");
delay(2000);
}