Use this when the user asks for aggregate reporting, counts, trends, or analysis requiring SQL over Graphite warehouse tables. Inspect relevant table metadata first. Executes one read-only SELECT or WITH statement scoped to the authenticated entity. Do not use for single-connection lookup, mutations, or guessed table or column names. Results are capped at 1,000 rows or 5 MiB; if truncated=true, aggregate or narrow the query and retry.