[KBM] Fix Action panel not showing for Text Expand trigger type

Manually sync SwitchPresenter.Value after programmatic ComboBox item
changes, since WinUI binding on SelectedItem.Tag does not reliably
update when items are cleared and replaced at runtime.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: Yu Leng (from Dev Box)

src/modules/keyboardmanager/KeyboardManagerEditorUI/Controls/UnifiedMappingControl.xaml.cs

@@ -1205,6 +1205,10 @@ private void SwitchActionTypeToReplaceWith()
             ActionTypeComboBox.Items.Add(replaceWithItem);
             ActionTypeComboBox.SelectedIndex = 0;
             ActionTypeComboBox.IsEnabled = false;
+
+            // Manually update SwitchPresenter since programmatic ComboBox item changes
+            // may not reliably trigger the SelectedItem.Tag binding update in WinUI.
+            ActionSwitchPresenter.Value = "ReplaceWith";
         }
 
         private void RestoreNormalActionTypes()
@@ -1223,6 +1227,12 @@ private void RestoreNormalActionTypes()
             _savedActionTypeItems = null;
             ActionTypeComboBox.SelectedIndex = 0;
             ActionTypeComboBox.IsEnabled = true;
+
+            // Manually sync SwitchPresenter with the restored first item's Tag.
+            if (ActionTypeComboBox.SelectedItem is ComboBoxItem selectedItem && selectedItem.Tag is string tag)
+            {
+                ActionSwitchPresenter.Value = tag;
+            }
         }
 
         #endregion