I want to create a Minecraft plugin that allows server operators to lock and unlock access to the Nether and End dimensions. Using commands like /lock nether or /lock end, operators will prevent players from entering those dimensions; the portals will still open, but when a player tries to enter, a green message will appear on their screen saying either "Nether is closed" or "End is closed." To re-enable access, operators will use /unlock nether or /unlock end. Only operators should have permission to lock or unlock, and only operators should be allowed to enter locked dimensions. The plugin should store the lock state in a config so that it persists after a server restart, and it should prevent unauthorized players from even attempting to enter once it's locked