Add cookie support and display yt-dlp version

[google-labs-jules]

This change addresses the "Too Many Requests" (HTTP 429) and "Sign in to confirm you’re not a bot" errors from YouTube by allowing users to provide their own cookies. It also displays the currently installed yt-dlp version in the footer to help verify if the tool is up-to-date.

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PR created automatically by Jules for task 6252439787902195845 started by @azman0101

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[semanticdiff-com]

Review changes with  

Changed Files

File	Status
app.py	32% smaller