Validate that a byte sequence is UTF-8-encoded text. All of these functions return zero when the byte sequence is not UTF-8-encoded text, and they return an unspecified non-zero value when the byte sequence is UTF-8-encoded text.

Variants are provided for both ByteArray# and Ptr. Additionally, variants are provided that use both the safe and unsafe FFI.

If compiling with SIMDUTF turned off, this module exports nothing.