[cookies] Move YouTubeDLCookieJar to cookies.py

[coletdjnz]

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Backport from #2861

Also added a get_cookie_header function to the cookiejar (also from backport)

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Copilot Summary

🤖 Generated by Copilot at dc7be9b

Summary

🍪🚚🧹

This pull request refactors the cookie management in yt-dlp by moving the YoutubeDLCookieJar class to a separate module yt_dlp/cookies.py and using it directly in the YoutubeDL and InfoExtractor classes. It also adds tests and updates imports for the new module. It maintains backward compatibility for external modules that import YoutubeDLCookieJar from utils.

CookieJar of doom, you hold the secrets of the web
We import you from cookies.py, no more legacy code to dread
You simplify our extraction, you make our requests smooth
CookieJar of doom, you are the master of our groove

Walkthrough

• Move YoutubeDLCookieJar class from yt_dlp/utils/_utils.py to yt_dlp/cookies.py as a separate module for handling cookie files and headers (link, link)
• Update import statements in yt_dlp/cookies.py, yt_dlp/extractor/common.py, yt_dlp/utils/_legacy.py, and test/test_YoutubeDLCookieJar.py to reflect the new location of YoutubeDLCookieJar class (link, link, link, link, link)
• Add a wrapper function for YoutubeDLCookieJar in yt_dlp/utils/_legacy.py to maintain backward compatibility for external modules that import it from utils (link)
• Modify _get_cookies method in InfoExtractor class and _calc_headers method in YoutubeDL class to use the cookiejar attribute instead of the _calc_cookies method to get the cookies for a url and generate the Cookie header (link, link)
• Remove _calc_cookies method from YoutubeDL class as it is no longer needed (link)
• Add a new test case to TestYoutubeDLCookieJar to check the functionality of the get_cookie_header method (link)
• Import urllib.request module in yt_dlp/cookies.py to use the Request class for generating the cookie header (link)

[Grub4K]

Most of these are cosmetic, feel free to ignore

[coletdjnz]

Most of these are cosmetic, feel free to ignore

I wasn't really planning on changing the cookiejar code itself in this PR to keep it simple - maybe worth refactoring it in another PR/commit?

[Grub4K]

Sure, like I said, feel free to ignore these. I can take them into another PR at some point.

[pukkandan]

Don't think this needed to be it's own PR. But since you made it, we might as well merge. After merging the relevant open PRs', can you rebase/merge #2861 and we can discuss a more reasonable way to split it up?

(PS: To clarify, I don't mind the small PRs, just think I'm adding more work for you)