Add cookies upload choice

Update poToken & visitorData input

Fix visibility of engine choice

Fix Error

Update options for different download engines

Change back to yt_dlp

Fix wrong args

change back to pytube

change to yt-dlp

Try web client

change back

Try different header

add proxy

Change to use proxy

Use tokens

Update YouTube object initialization to use "WEB"

Refactor video fetching and downloading logic to support adaptive streams and improve quality selection; add .gitignore for temporary files

Add initial implementation of YouTube video downloader with features for fetching, slicing, and downloading videos