/**
 * Internal RFC 4122 UUIDv5 (SHA-1 namespace hashing) — replaced the
 * external `uuid` package after its ESM-only major twice reached `dev`
 * via dependabot and broke strict-CJS consumers of the compiled `dist/`
 * with `ERR_REQUIRE_ESM` (the orchestrator's Vercel functions; see
 * `scripts/smoke-require.cjs` for the guard that now catches this class
 * in CI). scai only ever used `v5`, and v5 is fully specified — this
 * implementation is byte-identical to the package's output, which the
 * existing GUID-pinning tests prove (every recipe refKey derivation
 * would change otherwise, breaking recipe identity on re-push).
 *
 * Signature matches the `uuid` package's `v5(name, namespace)` string
 * form; the Buffer output variants scai never used are omitted.
 */
export declare const v5: (name: string | Uint8Array, namespace: string) => string;