[dariyaanis]

Summary

This PR completes the requested SDK review updates: runtime validation, public API documentation, one-scenario Promise examples, clearer README guidance, CI coverage, and a security policy.

Changes

• Validate required client and task parameters inside the SDK, including omitted constructor arguments.
• Validate proxy settings and conditional GeeTest v3/v4 parameters.
• Add unit coverage for valid and invalid task configurations.
• Add JSDoc examples for public client methods and every built-in task class.
• Replace misleading proxy-support crosses with a neutral marker and explanation.
• Remove the custom 10-second GeeTest polling interval.
• Consolidate examples into one Promise-chain suite using .then()/.catch().
• Ensure every example file performs exactly one API operation.
• Split proxy and proxyless scenarios into separate files.
• Split Image to Text and Coordinates variants into separate files.
• Update all README snippets and example links to match the new structure.
• Clarify solution response fields and add Important integration notes.
• Correct Turnstile User-Agent guidance to match the API documentation.
• Add Node.js 24 to the CI matrix.
• Run real-API integration tests on pull requests.
• Add SECURITY.md.

Validation

• npm run typecheck
• npm run test:unit -- --runInBand — 22 suites and 95 tests passed
• node --check for all 21 example scripts
• Real-API integration tests run in GitHub Actions