Release 0.4.0

Improve config watcher handling and user feedback

- Add RaiseConfigsChanged to manually trigger config reloads and watcher restart.
- Update Start/Stop methods to better manage ConfigsChanged event.
- Show debug output if config directory is missing.
- Clarify status messages for previous/invalid configs.
- Remove unused note boundary methods in MainWindow.xaml.cs.
- Immediately reload configs after changing config folder in settings.
- Enhances robustness and user experience when changing config folders.