Commit-Reveal Draw Verifier (static, offline, no server)

Pick the transcript.json written by main.py. Everything below runs locally in this tab via the browser's Web Crypto API -- nothing is uploaded anywhere. This is an independent re-implementation (JavaScript, not Python) of the same commit/HMAC/reveal check, so a PASS here proves the scheme is verifiable by a second party, not just by the code that produced it.