Introduce `closeAfterSave` callback to distinguish between save-and-close and cancel-and-close scenarios. Previously, saving settings would trigger `resetSettings()`, causing language changes to revert and requiring users to save twice for the change to take effect.
Changes:
- Add `closeAfterSave()`: close dialog without resetting settings after successful save
- Keep `closeDialog()`: reset settings when canceling or directly closing dialog
- Update save flow to use `closeAfterSave()` in `handleSaveClick`, `handleRestartLater`, and `handleRestartNow`