Port certificate lifecycle (parse/encrypt/upload/deactivate) and FiscalSeries CRUD from the auto, adapted to (product_id, tenant_ref, branch_ref) tenancy. Closes the "guard retroativo" PATCH /v1/series next_number regression check that Task 3 deferred to this task. Routes: POST/GET/DELETE /v1/certificados, POST/GET/PATCH /v1/series.