Are there no explanations or diagrams for Harmonic and Melodic Minor Modes?
None at the moment. I’ve thought about adding these kinds of modes but never got round to it. This site was initially intended for more general genres rather than hard core jazz stuff (not really my thing).
A few people have asked so maybe I’ll put it on the to-do list.
Personally, I think once you get to this point in guitar playing, if you need to know, or use these kinds of scales, then you should be at the point where you don’t really need lookup diagrams. I suppose there’s no harm in showing them for lookup and learning purposes though.
Saying that though, explanations of them would be useful. Even though I don’t use them personally, I do understand them so could write something about their basic usage and reasoning.