uuid: Missing buffer bounds check in `v3`/`v5`/`v6` when `buf` is provided

uuid is for the creation of RFC9562 (formerly RFC4122) UUIDs. Prior to 14.0.0, v3, v5, and v6 accept external output buffers but do not reject out-of-range writes (small buf or large offset). This allows silent partial writes into caller-provided buffers. This vulnerability is fixed in 14.0.0.