I understand, and it's a potentially useful tool but I think you'd be opening yourself up for a huge amount of liability with this app and I struggle to see the upside for you
I can't imagine ever being able to charge enough for its use to be worth the effort to create it, let alone worth the liability
The reality IMO is that very few cracks are expected in well-done construction: seeing cracks in your cladding or internal linings is usually an indication of a problem somewhere
So, inherently you want to be considering a professional opinion
My concern is that people are really lazy, dumb, and cheap. You stick something with "AI" on it that says "cosmetic crack" they're going to accept it as it's what they want to hear
People will also assess cracks in isolation whereas there needs to be a holistic view - where are the cracks, how many, how big, floor settlement pattern, other factors such as doors jamming, are the gutters overflowing outside, etc