I also recommend reading An ActivityPub Philosophy to place the standard in proper context and ForgeFed as an example of a federation protocol that is decidedly different than the most popular microblogging-based fediverse applications (PeerTube and PixelFed are nice examples of extensions to this category of apps).
Maybe at this point it is a good idea to move some activity to a repo. I am curious about the requirements for SolidLoV and find it hard to comment on e.g. what could be an Actor and what not.
Actors per the standard are persons, organizations, applications and services (though you can define your own custom extensions, of course). They have their own inbox, outbox endpoints and follower, following, likes collections, etc. But is an Ontology an Actor? Or is it a Document with Relationship to other documents (i.e. the reused ontologies on which it is based)?
In Mastodon the toots/tweets are Note and likes/favourites plus boosts/retweets are recorded as side-effects on the object.
The LoV application is very different from microblogging. It is about finding the right ontology from an ever growing archive, using them (and notifying about this so popularity can be measured), and publishing your own stuff to this archive… but my understanding of requirements is just so so 