cybreva/Car_Rental_System_CPP ? reverse-engineered prompt

Build me a simple C++ car rental system that runs in the console and lets a user manage cars and rentals from a menu.

I want to be able to add cars, view what cars are available, rent a car, return a car, and see basic rental details. Please keep it easy to use, with clear prompts and messages so someone can follow along without confusion. If it makes sense, store the car info and rental status in memory in a clean way using classes or structs, and keep the code organized even if it all lives in one file.

Make sure it handles common mistakes too, like trying to rent a car that is already rented or returning one that was not rented. Use standard C++ only if possible, and feel free to look up current docs online if you need to.