I have used AI agents extensively for coding and my experience is that it's fine for prototypes, but in large projects like this there is risk that the codebase becomes unmaintainable.
In large projects there is always a risk, if not an inevitability, that a code base becomes unmaintanable by some definition. AI surfaces this faster, but also AI lowers the cost of testing and refactoring. AI gives a linear multiplier in producing solutions, but complexity gives a quadratic increase in problems. The art of producing software has always been in choosing what not to do.