Back in March it looks like (yes, it's been a while since I updated zed) there was a change in the zed schema.go to error out if more than 1 namespace was found in a schema file on a write and copy. Was this check put in there because it's a "bad thing to do in spicedb" or as a sanity check for authzed? i.e. if it's the latter and I go about reading/writing the schema outside of zed into spicedb with multiple namespaces will bad things happen?