Configurable prompt

[hlidotbe]

Related to #63, being able to tailor the prompt would permit support for different conventions/templates. I tried by just adding a requirement to the prompt and it seems to give good results.

I'd rather not have to select the type like in #69, for me that defeats the purpose of generating the message. And it still possible to edit afterward.

[Seif-Mamdouh]

Hey @hlidotbe I forgot to update the screenshot in my PR but the AI automatically detect what type of conventional commit it is.

[hlidotbe]

Saw that, it's fine with GAC but unless I'm mistaken this doesn't work for the hook