feat: Add ROS 2 availability check and remove DroneController import.

scripts/run_ardupilot.py

@@ -31,8 +31,15 @@ except ImportError:
     print("Run: pip install pymavlink")
     sys.exit(1)
 
+try:
+    import rclpy
+    from rclpy.node import Node
+    ROS2_AVAILABLE = True
+except ImportError:
+    ROS2_AVAILABLE = False
+    print("[WARN] ROS 2 (rclpy) not available - using standalone controller")
+
 from config import ARDUPILOT, CONTROLLER, MAVLINK
-from src.drone_controller import DroneController
 
 
 class ArduPilotInterface: