feature/hls: Add HLS playback support, and refactors documentation for better usability and maintainability. (#1)

## Overview
This PR introduces HLS playback support, improves the player experience, and refactors documentation for better usability and maintainability.

## Key Features

### HLS Playback Support
- Add HLS integration via new JavaScript assets:
  - `hls.min.js`
  - `plyr.hls.start.js`
  - `watch.hls.js`
- Separate DASH and HLS logic:
  - `plyr-start.js` → `plyr.dash.start.js`
  - `watch.js` → `watch.dash.js`
- Update templates (`embed.html`, `watch.html`) for conditional player loading

### Native Storyboard Preview
- Add `native_player_storyboard` setting in `settings.py`
- Implement hover thumbnail preview for native player modes
- Add `storyboard-preview.js`

### UI and Player Adjustments
- Update templates and styles (`custom_plyr.css`)
- Modify backend modules to support new player modes:
  - `watch.py`, `channel.py`, `util.py`, and related components

### Internationalization
- Update translation files:
  - `messages.po`
  - `messages.pot`

### Testing and CI
- Add and update tests:
  - `test_shorts.py`
  - `test_util.py`
- Minor CI and release script improvements

## Documentation

### OpenRC Service Guide Rewrite
- Restructure `docs/basic-script-openrc/README.md` into:
  - Prerequisites
  - Installation
  - Service Management
  - Verification
  - Troubleshooting
- Add admonition blocks:
  - `[!NOTE]`, `[!TIP]`, `[!IMPORTANT]`, `[!WARNING]`, `[!CAUTION]`
- Fix log inspection command:
  ```bash
  doas tail -f /var/log/ytlocal.log
  ````

* Add path placeholders and clarify permission requirements
* Remove legacy and duplicate content

Reviewed-on: #1
Co-authored-by: Astounds <kirito@disroot.org>
Co-committed-by: Astounds <kirito@disroot.org>

youtube/yt_data_extract/__init__.py

@@ -10,4 +10,4 @@ from .watch_extraction import (extract_watch_info, get_caption_url,
     update_with_new_urls, requires_decryption,
     extract_decryption_function, decrypt_signatures, _formats,
     update_format_with_type_info, extract_hls_formats,
-    extract_watch_info_from_html, captions_available)
+    extract_watch_info_from_html, captions_available, parse_format)

youtube/yt_data_extract/watch_extraction.py

@@ -473,13 +473,22 @@ def _extract_formats(info, player_response):
         itag = yt_fmt.get('itag')
 
         # Translated audio track
-        # Example: https://www.youtube.com/watch?v=gF9kkB0UWYQ
-        # Only get the original language for now so a foreign
-        # translation will not be picked just because it comes first
-        if deep_get(yt_fmt, 'audioTrack', 'audioIsDefault') is False:
-            continue
+        # Keep non-default tracks for multi-audio support
+        # (they will be served via local proxy)
 
         fmt = {}
+
+        # Audio track info
+        audio_track = yt_fmt.get('audioTrack')
+        if audio_track:
+            fmt['audio_track_id'] = audio_track.get('id')
+            fmt['audio_track_name'] = audio_track.get('displayName')
+            fmt['audio_track_is_default'] = audio_track.get('audioIsDefault', True)
+        else:
+            fmt['audio_track_id'] = None
+            fmt['audio_track_name'] = None
+            fmt['audio_track_is_default'] = True
+
         fmt['itag'] = itag
         fmt['ext'] = None
         fmt['audio_bitrate'] = None
@@ -532,6 +541,61 @@ def _extract_formats(info, player_response):
     else:
         info['ip_address'] = None
 
+
+def parse_format(yt_fmt):
+    '''Parse a single YouTube format dict into our internal format dict.'''
+    itag = yt_fmt.get('itag')
+    fmt = {}
+
+    audio_track = yt_fmt.get('audioTrack')
+    if audio_track:
+        fmt['audio_track_id'] = audio_track.get('id')
+        fmt['audio_track_name'] = audio_track.get('displayName')
+        fmt['audio_track_is_default'] = audio_track.get('audioIsDefault', True)
+    else:
+        fmt['audio_track_id'] = None
+        fmt['audio_track_name'] = None
+        fmt['audio_track_is_default'] = True
+
+    fmt['itag'] = itag
+    fmt['ext'] = None
+    fmt['audio_bitrate'] = None
+    fmt['bitrate'] = yt_fmt.get('bitrate')
+    fmt['acodec'] = None
+    fmt['vcodec'] = None
+    fmt['width'] = yt_fmt.get('width')
+    fmt['height'] = yt_fmt.get('height')
+    fmt['file_size'] = extract_int(yt_fmt.get('contentLength'))
+    fmt['audio_sample_rate'] = extract_int(yt_fmt.get('audioSampleRate'))
+    fmt['duration_ms'] = yt_fmt.get('approxDurationMs')
+    fmt['fps'] = yt_fmt.get('fps')
+    fmt['init_range'] = yt_fmt.get('initRange')
+    fmt['index_range'] = yt_fmt.get('indexRange')
+    for key in ('init_range', 'index_range'):
+        if fmt[key]:
+            fmt[key]['start'] = int(fmt[key]['start'])
+            fmt[key]['end'] = int(fmt[key]['end'])
+    update_format_with_type_info(fmt, yt_fmt)
+    cipher = dict(urllib.parse.parse_qsl(multi_get(yt_fmt,
+        'cipher', 'signatureCipher', default='')))
+    if cipher:
+        fmt['url'] = cipher.get('url')
+    else:
+        fmt['url'] = yt_fmt.get('url')
+    fmt['s'] = cipher.get('s')
+    fmt['sp'] = cipher.get('sp')
+
+    hardcoded_itag_info = _formats.get(str(itag), {})
+    for key, value in hardcoded_itag_info.items():
+        conservative_update(fmt, key, value)
+    fmt['quality'] = hardcoded_itag_info.get('height')
+    conservative_update(fmt, 'quality',
+        extract_int(yt_fmt.get('quality'), whole_word=False))
+    conservative_update(fmt, 'quality',
+        extract_int(yt_fmt.get('qualityLabel'), whole_word=False))
+
+    return fmt
+
 hls_regex = re.compile(r'[\w_-]+=(?:"[^"]+"|[^",]+),')
 def extract_hls_formats(hls_manifest):
     '''returns hls_formats, err'''