CmdPal: Styling critical context items using the SystemFillColorCriticalBrush (#39645)

Styles context items based on the IsCritical property.


![image](https://github.com/user-attachments/assets/aa1ee0b0-de09-45af-8f5e-74dff666fbb4)


![image](https://github.com/user-attachments/assets/90a7f750-c949-4f76-b699-db2e29251414)

Closes #38307

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.WindowWalker/Components/ContextMenuHelper.cs

@@ -36,6 +36,7 @@ internal sealed class ContextMenuHelper
             contextMenu.Add(new CommandContextItem(new KillProcessCommand(windowData))
             {
                 RequestedShortcut = KeyChordHelpers.FromModifiers(true, false, false, false, (int)VirtualKey.Delete, 0),
+                IsCritical = true,
             });
         }