Document playlist export and new defaults

Update README to reflect new features and settings: add "Export Playlists" to the feature table; document the "Save Playlist As" export options (.txt, .csv, .m3u, .json). Add docs for Default Video Resolution and Default Subtitle Languages settings, and update the Output Filename Format variables to include %(playlist_index)s and %(resolution)s. These changes keep the README in sync with recent UI/settings additions.

README.md

@@ -72,6 +72,7 @@ YTSage is designed for users who want a **simple yet powerful YouTube downloader
 | 📜 Download History              | 🔄 Release Channel Selection            | 🌐 Proxy Support                   |
 | 🎚️ Audio Format Conversion       | 🎬 Video Format Settings                | 🆙 Built-in Updater Tab            |
 | 🌍 Generic Mode                   | 🔊 Audio Normalization (EBU R128)       | 🌍 Localization in 14 Languages    |
+| 💾 Export Playlists               | ⚙️ Default Quality & Subtitles          |         |
 </div>
 
 <a id="installation"></a>
@@ -262,7 +263,7 @@ python -m ytsage.main
 4. **Choose desired format/quality**
 5. **Click "Download"**
 
-> 💡 The application automatically handles the download queue
+> 💡 The application automatically handles the download queue, and you can export the playlist entries to `.txt`, `.csv`, `.m3u`, or `.json` using the **Save Playlist As** button.
 
 </details>
 
@@ -305,7 +306,9 @@ Notes:
 
 - **Speed Limiter:** Limit the download speed, for example `500K` for 500 KB/s
 - **Save Download Path:** Save the default download path for future downloads. Available in **Download Settings → Download Path**.
-- **Output Filename Format:** Customize the output filename format using variables like `%(title)s`, `%(uploader)s`, and `%(resolution)s`. Available in **Download Settings → Filename Format**.
+- **Default Video Resolution:** Set your preferred default video resolution for automatic selection (e.g., 1080p, 720p). Available in **Download Settings → Default Video Resolution**.
+- **Default Subtitle Languages:** Set default subtitle languages to auto-select automatically (comma-separated, e.g., `en,es`). Available in **Download Settings → Default Subtitle Languages**.
+- **Output Filename Format:** Customize the output filename format using variables like `%(title)s`, `%(uploader)s`, `%(playlist_index)s`, and `%(resolution)s`. Available in **Download Settings → Filename Format**.
 - **Force Output Format:** Force video downloads into a specific container format such as `mp4`, `webm`, or `mkv`. Available in **Download Settings → Output Format Settings**.
 - **Audio Format Conversion:** Convert audio-only downloads to preferred formats such as `AAC`, `MP3`, `FLAC`, `WAV`, `Opus`, `M4A`, `Vorbis`, or `Best`. Available in **Download Settings → Audio Format Settings**.
 - **Audio Normalization:** Standardize volume for audio-only downloads using EBU R128.