* feat(skills): add saas-multi-tenant — multi-tenant SaaS architecture with RLS, tenant-scoped queries, and isolation patterns * chore: sync generated registry files * fix: address code review — set_config, cleanup, args guard, findUnique * chore(pr411): Remove derived artifacts * chore(pr411): Drop derived files from diff * chore(pr411): Revert count drift --------- Co-authored-by: sickn33 <sickn33@users.noreply.github.com>