feat: add stealth mode and enhance undetected browser support

- Add playwright-stealth integration with enable_stealth parameter in BrowserConfig
- Merge undetected browser strategy into main async_crawler_strategy.py using adapter pattern
- Add browser adapters (BrowserAdapter, PlaywrightAdapter, UndetectedAdapter) for flexible browser switching
- Update install.py to install both playwright and patchright browsers automatically
- Add comprehensive documentation for anti-bot features (stealth mode + undetected browser)
- Create examples demonstrating stealth mode usage and comparison tests
- Update pyproject.toml and requirements.txt with patchright>=1.49.0 and other dependencies
- Remove duplicate/unused dependencies (alphashape, cssselect, pyperclip, shapely, selenium)
- Add dependency checker tool in tests/check_dependencies.py

Breaking changes: None - all existing functionality preserved

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

mkdocs.yml

@@ -45,6 +45,7 @@ nav:
     - "Lazy Loading": "advanced/lazy-loading.md"
     - "Hooks & Auth": "advanced/hooks-auth.md"
     - "Proxy & Security": "advanced/proxy-security.md"
+    - "Undetected Browser": "advanced/undetected-browser.md"
     - "Session Management": "advanced/session-management.md"
     - "Multi-URL Crawling": "advanced/multi-url-crawling.md"
     - "Crawl Dispatcher": "advanced/crawl-dispatcher.md"