feat: add JavaScript/TypeScript client SDK

[leoneperdigao]

Description

Build a JavaScript/TypeScript client SDK for consuming the QRNG API from both browser and Node.js environments. The SDK should provide TypeScript type definitions, handle retries, and integrate with the Web Crypto API for browser-based cryptographic applications.

Tasks

• Create @taoq-ai/qrng-client npm package with TypeScript source
• Implement client class with methods:
  • client.randomBytes(count: number): Promise<Uint8Array>
  • client.randomIntegers(min: number, max: number, count: number): Promise<number[]>
  • client.randomUUID(): Promise<string>
  • client.randomGaussian(mean: number, stddev: number, count: number): Promise<number[]>
  • client.health(): Promise<HealthStatus>
• Support both browser (fetch API) and Node.js (node-fetch / undici) environments
• Bundle TypeScript type definitions (.d.ts files) with the package
• Implement automatic retry with exponential backoff
• Add configurable timeout and base URL
• Provide Web Crypto API integration:
  • QRNGCryptoProvider implementing Crypto.getRandomValues() using QRNG backend
• Support ESM and CommonJS module formats
• Write tests with mocked HTTP responses (vitest or jest)
• Set up npm publishing workflow (GitHub Actions)
• Write usage documentation with code examples for browser and Node.js

References

• Web Crypto API
• fetch API