Complete Integration Testing and Documentation (#130)

Task 25 - Complete Integration Testing:
- Create comprehensive integration test suite (test_complete_integration.cc)
- Test example server startup and health checks
- Verify public tool access without authentication
- Test protected tools require authentication
- Implement OAuth flow simulation tests
- Add concurrent token validation tests (thread safety)
- Test token expiration handling
- Add performance benchmarks
- Create integration test runner script
- Include memory leak detection preparation

Task 26 - Documentation and Cleanup:
- Create AUTH_BUILD_GUIDE.md with platform-specific build instructions
- Document dependencies, configuration, and troubleshooting
- Create AUTH_API_REFERENCE.md with complete API documentation
- Include code examples and usage patterns
- Document performance metrics and benchmarks
- Clean up debug logging statements
- Document differences from Node.js implementation
- Add security considerations

Both tasks complete the JWT authentication implementation with
comprehensive testing and documentation.

Author: RahulHere