Add crypto-utils building block using Noble crypto libraries

[ejacquier]

Summary

Adds a new crypto-utils building block that demonstrates how to use cryptographic operations in CRE TypeScript workflows using the Noble crypto libraries as an alternative to the Node.js crypto module.

Why this is needed

The CRE TypeScript SDK runs on QuickJS, which doesn't support Node.js native modules. This means require('crypto') doesn't work. Noble libraries are pure JavaScript and work perfectly in QuickJS.

What's included

• Hashing: SHA-256, SHA-384, SHA-512, SHA3-256, SHA3-512, Keccak-256, BLAKE2b, BLAKE3, RIPEMD-160
• HMAC: HMAC-SHA256, HMAC-SHA512, HMAC-SHA3-256
• Key Derivation: PBKDF2, Scrypt, HKDF
• Symmetric Encryption: AES-256-GCM, ChaCha20-Poly1305
• Digital Signatures: ECDSA (secp256k1), Ed25519
• Key Exchange: ECDH (secp256k1), X25519
• Random Bytes: Custom implementation using CRE's Math.random() polyfill (ChaCha8Rng)
• Real-world examples: Bitcoin and Ethereum address derivation

Random bytes

Noble's randomBytes() fails because it needs crypto.getRandomValues, but CRE provides a Math.random() polyfill using ChaCha8Rng that is consensus-safe. The template shows how to build your own randomBytes():

function randomBytes(length: number): Uint8Array {
  const bytes = new Uint8Array(length);
  for (let i = 0; i < length; i++) {
    bytes[i] = Math.floor(Math.random() * 256);
  }
  return bytes;
}

Documentation

• Complete Node.js crypto → Noble library mapping table with code references
• Setup and running instructions
• Use case examples with code snippets

Test plan

• Workflow compiles successfully
• cre workflow simulate workflow runs without errors
• All crypto operations produce valid output
• Signature verification returns true
• ECDH shared secrets match between parties
• Encryption/decryption roundtrip works

[github-actions]

👋 ejacquier, thanks for creating this pull request!

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[timothyF95]

nit: The latest version of CLI changed the naming from chain-id to chain-selector smartcontractkit/cre-cli#252