Notarize a public URL: we fetch it ourselves and return a signed snapshot (final URL, HTTP status, content-type, sha256 of the body, server timestamp, upstream host) with TWO cryptographic attestations — a plain EIP-712 signature and an EAS off-chain (Version2) attestation. Proves what this endpoint observed at fetch time (integrity + timestamp + non-repudiation). mode=hash (default) returns metadata + hash only; mode=full also returns the body.