KongConsumerGroups were still named sttlab-user/sttlab-admin, a leftover
from before the classic-models realm's role model existed. Real users'
JWTs carry realm roles (admin, read_only, product_manager, customer,
support) via consumer_groups_claim, so no group ever matched and every
tool call was rejected with 403 "consumer groups were not found".
Groups now match the realm roles directly; tool ACLs gate on each role's
catalog:read/catalog:write grant from security-model.yaml.