Adding StartupNotifier

src/main/java/se/urmo/electricityalert/notifier/StartupNotifier.java

@@ -0,0 +1,29 @@
+package se.urmo.electricityalert.notifier;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.context.event.ApplicationReadyEvent;
+import org.springframework.context.event.EventListener;
+import org.springframework.stereotype.Component;
+
+@Component
+public class StartupNotifier {
+    private static final Logger log = LoggerFactory.getLogger(StartupNotifier.class);
+
+    private final TelegramNotifier telegramNotifier;
+
+    public StartupNotifier(TelegramNotifier telegramNotifier) {
+        this.telegramNotifier = telegramNotifier;
+    }
+
+    @EventListener(ApplicationReadyEvent.class)
+    public void notifyStartup() {
+        String msg = "🔄 Electricity Alert Service has restarted and is running.";
+        try {
+            telegramNotifier.send(msg);
+            log.info("Sent startup notification: {}", msg);
+        } catch (Exception e) {
+            log.warn("Failed to send startup notification", e);
+        }
+    }
+}