fix the native blake2 bindings issue

[kamalbuilds]

Fixes #13

The issue is that the sdk is trying to use the native blake2 Node.js module which requires C++ bindings, but those bindings aren't available.

However, there are pure JavaScript/TypeScript implementations of BLAKE2 that we can use instead and in this PR uses it.

The advantages of this approach are:

1. No native dependencies required
2. Pure JavaScript implementation that works in all environments
3. Well-maintained and secure implementation
4. TypeScript support out of the box

The @noble/hashes library is a popular choice for cryptographic hashes in JavaScript/TypeScript projects and provides a more portable solution than the native blake2 module. It implements the same BLAKE2b algorithm, so the cryptographic properties and output will be identical to the native version.

[Copilot]

Pull Request Overview

This pull request replaces the native Node.js C++ BLAKE2 bindings with a pure JavaScript implementation using the @noble/hashes library to improve portability and remove native dependencies.

• Removed the native blake2 import and usage.
• Added the @noble/hashes/blake2b implementation with the appropriate digest length configuration.