This simple datapack adds one new item, the Security Detector. If you place one, it automatically links to the nearest player, so you. When it detects any player in its 15 block radius, it will alert the player it is linked to. Every player can only be linked to one detector, so if you place a new one, the old one will be destroyed.
Note: To obtain this new item, type /function give_security_detector in the chat.