1. history schema versions , who edit the schema? Edited what? 2. why we need so many instances if we have different schema?

It's possible to enrich with metadata today via comments. You can retrieve the comments with the new Reflection API. You can basically turn that into your own schema metadata.

Alright

and at least in our system, the schema is something that's held in github and deployed to SpiceDB via a CI task. our wrapper service doesn't expose access to the schema endpoint at all.