[ie/twitter:broadcast] Support --wait-for-video

[bashonly]

Closes #8473

Template

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Copilot Summary

🤖 Generated by Copilot at e636a95

Summary

🕒🔄🔧

Improved periscope and twitter extractors to handle live broadcasts better. Added live_status field to indicate the current state of the video, and skipped downloading videos that are not yet available.

Sing, O Muse, of the cunning code review
That made the TwitterBroadcastIE more wise
And taught it to avoid the videos due
That have not yet appeared before the eyes.

Walkthrough

• Import traverse_obj function from utils.py to access nested values in a dictionary or a list (link)
• Replace is_live field with live_status field in _parse_broadcast_data function to handle different states of broadcasts (link, link)
• Update timestamp and release_timestamp fields in _parse_broadcast_data function to parse ISO 8601 date string and convert milliseconds to seconds (link)
• Return early from _real_extract function in TwitterBroadcastIE class if live_status is is_upcoming to avoid unnecessary requests and errors (link)