feat: Enhance main loop with error handling and graceful shutdown

main.py

@@ -295,6 +295,7 @@ max_ntp_attempts = 5  # Try up to 5 times after initial failure
 # ===== START: Main Loop =====
 # Main monitoring loop (runs forever until Ctrl+C)
 while True:
+    try:
         # Run all monitors (each checks if it's time to run via should_run())
         run_monitors(monitors)
 
@@ -315,7 +316,30 @@ while True:
                 if retry_ntp_attempts == 0 or (time.time() % 10) < 1:
                     retry_ntp_attempts += 1
                     print("NTP retry {} failed: {}".format(retry_ntp_attempts, e))
-
+        # Enable garbage collection to free memory
         gc.collect()
         time.sleep(0.1)
+        
+    except KeyboardInterrupt:
+        # Graceful shutdown on Ctrl+C
+        print("\n\n" + "="*50)
+        print("Shutting down gracefully...")
+        print("="*50)
+        print("Turning off AC...")
+        ac_controller.turn_off()
+        print("Turning off heater...")
+        heater_controller.turn_off()
+        print("Turning off LED...")
+        led.low()
+        print("Shutdown complete!")
+        print("="*50 + "\n")
+        break
+        
+    except Exception as e:
+        # If loop crashes, print error and keep running
+        print("❌ Main loop error: {}".format(e))
+        import sys
+        sys.print_exception(e)
+        print("⚠️ Pausing 5 seconds before retrying...")
+        time.sleep(5)  # Brief pause before retrying
 # ===== END: Main Loop =====