Implement FDE cycle

[github-actions]

This should be done in `cpu.cpp`

TRV-Emu/include/cpu.hpp

Line 6 in 62bf0db

// TODO: Implement FDE cycle

#include "memory.hpp"

// TODO: Implement FDE cycle
// This should be done in `cpu.cpp`
class CPU {
    public:
        CPU(Memory* memory);