⚠️ A real miniature blockchain demo — it does NOT record "reality",
only the events you type. Tamper-evidence works only inside this
demo chain; there is no distributed network, no consensus, no external truth source.
Paste the JSON export of a chain (see demo.py → export.json), then press Verify.
This page re-computes every SHA-256 hash with crypto.subtle and checks every link.