[extractor/twitcasting] Twitcasting Live webpage changed

[JC-Chung]

The old _search_regex in TwitCastingLiveIE is no longer available.

IMPORTANT: PRs without the template will be CLOSED

Description of your pull request and other information

r'data-type="movie" data-id="(\d+)">',
r'tw-sound-flag-open-link" data-id="(\d+)" style=',
r'(?s)(<span\s*class="tw-movie-thumbnail-badge"\s*data-status="live">\s*LIVE)' and
r'(?s)<a\s+class="tw-movie-thumbnail"\s*href="/[^/]+/movie/(?P<video_id>\d+)"\s*>.+?</a>' now no available in webpage.

Fixes #

Template

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• At least skimmed through contributing guidelines including yt-dlp coding conventions
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• Checked the code with flake8 and ran relevant tests

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• Fix or improvement to an extractor (Make sure to add/update tests)
• New extractor (Piracy websites will not be accepted)
• Core bug fix/improvement
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Copilot Summary

🤖 Generated by Copilot at 06c1eb6

Summary

🐛🚨📺

Improve live stream extraction and error handling for twitcasting extractor. Use HTML attributes instead of regexes to get stream status and id.

Sing, O Muse, of the skillful twitcasting extractor
That deftly discerns the live streams from the silent ones
And gracefully handles the errors of offline users
With attributes more trustworthy than the old regexes

Walkthrough

• Add a check for the data-is-onlive attribute to determine the live status of the user (link, link)
• Raise a UserNotLive exception if the user is not live, instead of returning an empty playlist (link)
• Add another regex to match the data-movie-id attribute as a possible source of the live ID (link)