[PMDG 777ER] Thanzo Cabin Light

The Thanzo Cabin Light add-on for the PMDG 777-300ER enhances the cabin lighting by replacing the standard yellowish ambient light with a brighter white light, improving overall visibility. This version also addresses previous issues with cabin shadows during night flights. The update adds functional backlighting for seats and luggage racks while maintaining compatibility with custom liveries. A shader cache reset is suggested for optimal performance, with a utility provided to assist in this process.