Adding the option to enter a description

[yermak]

Discussed in #659

^{Originally posted by Meldrod April 29, 2025}
Hello, I noticed that instead of being able to add a commentary I would rather enter different metadata. For instance a description of the audiobook. I would appreciate this ability as it is very tedious to add these kind of metadata afterwards. Please add this. Or even the option to add all kinds of metadata while converting. Thank you