fix: remove non-functional save_recording_path parameter
- Remove save_recording_path field from BrowserProfile class
- Remove documentation for save_recording_path parameter
- Add migration note directing users to use record_video_dir instead
The save_recording_path parameter was defined in BrowserProfile but never actually
processed by the browser launch methods. Users should use the standard Playwright
record_video_dir parameter instead, which is properly implemented and functional.
Fixes user reports of video recording not working when using save_recording_path.