TDD RED phase - tests expect ZhihuLogin class that doesn't exist yet:
- test_login_page_access: verify correct login URL
- test_qrcode_screenshot: verify QR code capture and save
- test_cookie_detection_with_z_c0: verify login detection
- test_cookie_detection_without_z_c0: verify no login when missing z_c0
- test_cookie_extraction: verify cookie string format
- test_login_timeout: verify timeout after 60s polling
- test_result_model_success: verify success result model
- test_result_model_failure: verify failure result model
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
