- Added AppendSuffix bool field to convertConfig (default: false)
- By default, output filename matches source filename exactly
- Added checkbox "Append \"-convert\" to filename" (unchecked by default)
- Checkbox appears in both Simple and Advanced modes
- Eliminates noise when doing batch conversions
- Auto-naming still works and respects the suffix setting
Before: video.mp4 → video-convert.mp4 (always)
After: video.mp4 → video.mp4 (or video-convert.mp4 if checked)
