Repository: yt-dlp
Issue: [XiaoHongShu] add H.265/HEVC extraction
Labels: site-enhancement,triage

### DO NOT REMOVE OR SKIP THE ISSUE TEMPLATE

- [x] I understand that I will be **blocked** if I *intentionally* remove or skip any mandatory\* field

### Checklist

- [x] I'm requesting a site-specific feature
- [x] I've verified that I have **updated yt-dlp to nightly or master** ([update instructions](https://github.com/yt-dlp/yt-dlp#update-channels))
- [x] I've checked that all provided URLs are playable in a browser with the same IP and same login details
- [x] I've searched [known issues](https://github.com/yt-dlp/yt-dlp/issues/3766) and the [bugtracker](https://github.com/yt-dlp/yt-dlp/issues?q=) for similar issues **including closed ones**. DO NOT post duplicates
- [x] I've read the [guidelines for opening an issue](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#opening-an-issue)
- [x] I've read about [sharing account credentials](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#are-you-willing-to-share-account-details-if-needed) and I'm willing to share it if required

### Region

Global

### Example URLs

https://www.xiaohongshu.com/explore/676ccedd000000000900d4c7?xsec_token=ABl8MasLC9VFpJwsLb3pHTYMetZWyCyL29364bw6B3sKM=&xsec_source=pc_feed

### Provide a description that is worded well enough to be understood

The platform provides H.265/HEVC encodes for popular videos (example URL is a random video from the home page that has an H.265/HEVC encode available at "https://sns-video-ak.xhscdn.com/stream/1/110/4/01e76cc9b322080a010370039401096085_4.mp4", but yt-dlp currently only finds/extracts the H.264/AVC video stream.
audio stream seems to be the same VBR 56 kbps 44.1 Khz HE-AAC audio track that's used for the H.264/AVC video stream.

### Provide verbose output that clearly demonstrates the problem

- [x] Run **your** yt-dlp command with **-vU** flag added (`yt-dlp -vU <your command line>`)
- [x] If using API, add `'verbose': True` to `YoutubeDL` params instead
- [x] Copy the WHOLE output (starting with `[debug] Command-line config`) and insert it below

### Complete Verbose Output

```shell
R:\>yt-dlp -vU -F https://www.xiaohongshu.com/explore/676ccedd000000000900d4c7?xsec_token=ABl8MasLC9VFpJwsLb3pHTYMetZWyCyL29364bw6B3sKM=&xsec_source=pc_feed
[debug] Command-line config: ['-vU', '-F', 'https://www.xiaohongshu.com/explore/676ccedd000000000900d4c7?xsec_token=ABl8MasLC9VFpJwsLb3pHTYMetZWyCyL29364bw6B3sKM=']
[debug] Portable config "C:\Program Files (x86)\yt-dlp\yt-dlp.conf": ['-S', 'res,vcodec:av1']
[debug] Encodings: locale cp1252, fs utf-8, pref cp1252, out utf-8, error utf-8, screen utf-8
[debug] yt-dlp version stable@2025.01.15 from yt-dlp/yt-dlp [c8541f8b1] (win_exe)
[debug] Python 3.10.11 (CPython AMD64 64bit) - Windows-10-10.0.22631-SP0 (OpenSSL 1.1.1t  7 Feb 2023)
[debug] exe versions: ffmpeg git-2024-10-01-7151081-ffmpeg-windows-build-helpers (fdk,setts)
[debug] Optional libraries: Cryptodome-3.21.0, brotli-1.1.0, certifi-2024.12.14, curl_cffi-0.5.10, mutagen-1.47.0, requests-2.32.3, sqlite3-3.40.1, urllib3-2.3.0, websockets-14.1
[debug] Proxy map: {}
[debug] Request Handlers: urllib, requests, websockets, curl_cffi
[debug] Loaded 1837 extractors
[debug] Fetching release info: https://api.github.com/repos/yt-dlp/yt-dlp/releases/latest
Latest version: stable@2025.01.15 from yt-dlp/yt-dlp
yt-dlp is up to date (stable@2025.01.15 from yt-dlp/yt-dlp)
[XiaoHongShu] Extracting URL: https://www.xiaohongshu.com/explore/676ccedd000000000900d4c7?xsec_token=ABl8MasLC9VFpJwsLb3pHTYMetZWyCyL29364bw6B3sKM=
[XiaoHongShu] 676ccedd000000000900d4c7: Downloading webpage
[debug] Sort order given by user: res, vcodec:av1
[debug] Formats sorted by: hasvid, ie_pref, res, vcodec:av1(11), lang, quality, fps, hdr:12(7), channels, acodec, size, br, asr, proto, vext, aext, hasaud, source, id
[info] Available formats for 676ccedd000000000900d4c7:
ID EXT RESOLUTION FPS CH │  FILESIZE      TBR PROTO │ VCODEC      VBR ACODEC    ABR
───────────────────────────────────────────────────────────────────────────────────
0  mp4 720x1280    30  2 │  37.54MiB 3804724k http  │ h264   3742971k aac    56116k
1  mp4 720x1280    30  2 │  37.54MiB 3804724k http  │ h264   3742971k aac    56116k
"xsec_source" non è riconosciuto come comando interno o esterno,
 un programma eseguibile o un file batch.
```