dominicrume/cantor8_kya_rails: step-3-verify/THE-JOB.md

# JOB: step-3-verify IN: receipts.js written by the agent DO: one self-contained page: WhatsApp-style chat replay + receipt chain panel + VERIFY button (recomputes every seal) + TAMPER button (edits one receipt, chain cascades red) OUT: verifier.html, double-click to open, works with no network at a