Mabey use patchouli as an optional dependency to implement an in game guide

You could also internally integrate patchouli so there is no dependency

Afaik, the Forbiddenomicon will be the in-game guidebook and will not use Patchouli due to how the devs want it to function.

Yes we plan to create our own guidebook which is planned for one of the next updates. Writing a Patchouli one before would mostly be a waste of our resources as we could spend that time on new features.