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/i18n_strings.py

@@ -110,3 +110,32 @@ OPTIONS = _l('Options')
 SETTINGS = _l('Settings')
 ERROR = _l('Error')
 LOADING = _l('loading...')
+
+# Settings option values
+TOP = _l('Top')
+NEWEST = _l('Newest')
+AUTO = _l('Auto')
+ENGLISH = _l('English')
+ESPANOL = _l('Español')
+
+# Playback options
+AUTO_HLS_PREFERRED = _l('Auto (HLS preferred)')
+FORCE_HLS = _l('Force HLS')
+FORCE_DASH = _l('Force DASH')
+RANKING_1 = _l('#1')
+RANKING_2 = _l('#2')
+RANKING_3 = _l('#3')
+
+# Form actions
+SAVE_SETTINGS = _l('Save settings')
+
+# Other category
+OTHER = _l('Other')
+
+# Settings labels
+PLAYBACK_MODE = _l('Playback mode')
+
+# Subscription settings (may be used in future)
+AUTOCHECK_SUBSCRIPTIONS = _l('Autocheck subscriptions')
+INCLUDE_SHORTS_SUBSCRIPTIONS = _l('Include shorts in subscriptions')
+INCLUDE_SHORTS_CHANNEL = _l('Include shorts in channel')