fix(ui): show wizard as modal dialog

* Switches wizard launch to `show()` + `setModal(true)` for consistent
  modal behavior across platforms
* Removes close-delete, macOS dialog flag, `open()`, and deferred
  raise/activate logic to avoid focus/stacking issues

Author: saturneric

src/ui/main_window/MainWindowSlotUI.cpp

@@ -46,19 +46,8 @@ void MainWindow::SlotSetStatusBarText(const QString& text) {
 
 void MainWindow::slot_start_wizard() {
   auto* wizard = new Wizard(this);
-  wizard->setAttribute(Qt::WA_DeleteOnClose);
-  wizard->setWindowModality(Qt::ApplicationModal);
-
-#ifdef Q_OS_MACOS
-  wizard->setWindowFlag(Qt::Dialog, true);
-#endif
-
-  wizard->open();
-
-  QTimer::singleShot(0, wizard, [wizard]() {
-    wizard->raise();
-    wizard->activateWindow();
-  });
+  wizard->show();
+  wizard->setModal(true);
 }
 
 void MainWindow::slot_maybe_show_wizard() {