I don’t see consciousness as some special mental faut or whatever.
In my mind it’s a social mechanism meant to allow a more nuanced, complex and deliberate reaction to the world around it and it’s community versus a creature purely with instinct.
In my eyes then, we will know that an AI is conscious if overtime it varies it’s actions and reactions based in a way that it assumes will help guarantees its existence and future usefulness versus it’s prompt varying because that’s how X spoke to it 1 million times.