lmdb: `NostrLmdb::reindex` is dangerous

[TheAwiteb]

So, it sounds helpful, like it just "reindexes" the database, but in fact, it also deletes trackers, like deleted events and vanished users. Because of this, the database will accept them again when it shouldn't.

Deleting trackers makes sense when wiping the database, but not when reindexing it. I think we should have something like Lmdb::wipe_trackers and only call it on wipe, while keeping Lmdb::wipe_indexes strictly for indexes, the things that can actually be reindexed.

I'm not sure if this is a bug or not, so just leave it as an idea.

[TheAwiteb]

I'm sure that we can rebuild deleted_ids, deleted_coordinates and vanished_public_keys, but I'm not sure why we don't do this, maybe because we will do what we did when we saved the event? I just think it's easier to just not wipe them unless on database wipe, not reindex