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/comments.py

@@ -155,33 +155,35 @@ def post_process_comments_info(comments_info):
 
 
 def video_comments(video_id, sort=0, offset=0, lc='', secret_key=''):
+    if not settings.comments_mode:
+        return {}
+
+    # Initialize the result dict up-front so that any exception path below
+    # can safely attach an 'error' field without risking UnboundLocalError.
+    comments_info = {'error': None}
     try:
-        if settings.comments_mode:
-            comments_info = {'error': None}
-            other_sort_url = (
-                util.URL_ORIGIN + '/comments?ctoken='
-                + make_comment_ctoken(video_id, sort=1 - sort, lc=lc)
-            )
-            other_sort_text = 'Sort by ' + ('newest' if sort == 0 else 'top')
+        other_sort_url = (
+            util.URL_ORIGIN + '/comments?ctoken='
+            + make_comment_ctoken(video_id, sort=1 - sort, lc=lc)
+        )
+        other_sort_text = 'Sort by ' + ('newest' if sort == 0 else 'top')
 
-            this_sort_url = (util.URL_ORIGIN
-                             + '/comments?ctoken='
-                             + make_comment_ctoken(video_id, sort=sort, lc=lc))
+        this_sort_url = (util.URL_ORIGIN
+                         + '/comments?ctoken='
+                         + make_comment_ctoken(video_id, sort=sort, lc=lc))
 
-            comments_info['comment_links'] = [
-                (other_sort_text, other_sort_url),
-                ('Direct link', this_sort_url)
-            ]
+        comments_info['comment_links'] = [
+            (other_sort_text, other_sort_url),
+            ('Direct link', this_sort_url)
+        ]
 
-            ctoken = make_comment_ctoken(video_id, sort, offset, lc)
-            comments_info.update(yt_data_extract.extract_comments_info(
-                request_comments(ctoken), ctoken=ctoken
-            ))
-            post_process_comments_info(comments_info)
+        ctoken = make_comment_ctoken(video_id, sort, offset, lc)
+        comments_info.update(yt_data_extract.extract_comments_info(
+            request_comments(ctoken), ctoken=ctoken
+        ))
+        post_process_comments_info(comments_info)
 
-            return comments_info
-        else:
-            return {}
+        return comments_info
     except util.FetchError as e:
         if e.code == '429' and settings.route_tor:
             comments_info['error'] = 'Error: YouTube blocked the request because the Tor exit node is overutilized.'