cr.sha carried SHA-384 and SHA-512 from cm.sha verbatim but the README understated it as SHA-256+SHA-384 only. Docs and tests now reflect the full three-family SHA-2 surface: SHA-256 / 384 / 512 each with Init/Update/Final + Buffer/String one-shot + DigestToHex + DigestEqual helpers. Test vectors for all three added.