NHK metadata fixes/improvements

[garret1317]

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Description of your pull request and other information

This PR fixes/improves NHK World's metadata extraction.
I've also snuck in a little change to NHK Radiru (domestic radio) while i'm here

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The titles of one-off programmes, like https://www3.nhk.or.jp/nhkworld/en/ondemand/video/3004952/, were somewhat borked. The API returns the (sub)title as <p></p>, so the title the extractor returned was Barakan Discovers AMAMI OSHIMA: Isson's Treasure Island - <p></p>

the site doesn't handle it that well either tbh, note the - at the start

I've made it so that the series Barakan Discovers AMAMI OSHIMA: Isson's Treasure Island becomes the title, and the series becomes None - it's a one-off, so it's not really in a series.

In doing this, I changed the criteria for returning series/episode slightly. One-offs have no series. If there is no series, there can't be an episode of it, so episode isn't returned either.

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If a programme had no entries, e.g. the sumo (first test), the extraction (or at least, the test) would fail, as it couldn't get the series from the nonexistent entries.

By extracting from the programme page instead, we prevent this, and gain the description "for free" as well

we could also get the thumbnail:

thumbnail_div = get_element_by_class('p-programDetail__itemImg', html)
thumbnail = extract_attributes(thumbnail_div).get('src')  # the div contains nothing but an <img> tag

but it's a relative url, cba to urljoin it
+ too much potential for fatalities/borking

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The streams API has some other metadata, mostly related to timestamps.
I modified the _extract_formats_and_subtitles to extract this additional info as well.
It does rather ruin how nice and elegant it was before, i'm afraid
but got to get the metadata somehow

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the radiru change
I've set the station name as uploader (in addition to channel, which it already is)

this is purely so i can have the station name embedded as the artist without changing my config
that commit can be skipped if thats not a valid enough reason

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Template

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• Searched the bugtracker for similar pull requests
• 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

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Summary

🌐🎧📺

This pull request enhances the support for downloading videos and audio from the NHK website and API. It fixes and updates the extraction of titles, descriptions, thumbnails, formats, subtitles, and other metadata for the NhkVodIE, NhkVodProgramIE, NhkRadiruIE, and NhkRadioNewsPageIE extractors. It also adds or updates tests for these extractors in the file yt_dlp/extractor/nhk.py.

NhkVodIE and more
Extract fields from website, API
Autumn tests updated

Walkthrough

• Rename and modify _extract_formats_and_subtitles function to return additional stream information (link, link)
• Use clean_html function to sanitize title, sub_title, and description fields in _extract_episode_info function (link)
• Handle missing or empty series and title fields in _extract_episode_info function and update info dictionary with stream information (link)
• Extract program title and description from HTML page in NhkVodProgramIE extractor (link)
• Extract uploader field from API response in NhkRadiruIE extractor (link)
• Import clean_html and get_element_by_class functions from utils module (link)
• Add test cases for NhkVodIE extractor with additional fields and fix description typo (link, link, link, link)
• Add description field and update playlist_mincount for test cases for NhkVodProgramIE extractor (link, link, link)
• Add uploader field for test cases for NhkRadiruIE extractor (link, link, link, link, link)