CmdPal: Handle CommandItem Title changes properly and raise notification every time it changes (#40513)

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- [x] **Closes:** #39167 
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src/modules/cmdpal/Microsoft.CmdPal.Core.ViewModels/CommandItemViewModel.cs

@@ -313,6 +313,10 @@ public partial class CommandItemViewModel : ExtensionObjectViewModel, ICommandBa
 
                 Command = new(model.Command, PageContext);
                 Command.InitializeProperties();
+
+                // Extensions based on Command Palette SDK < 0.3 CommandItem class won't notify when Title changes because Command
+                // or Command.Name change. This is a workaround to ensure that the Title is always up-to-date for extensions with old SDK.
+                _itemTitle = model.Title;
                 UpdateProperty(nameof(Name));
                 UpdateProperty(nameof(Title));
                 UpdateProperty(nameof(Icon));
@@ -385,6 +389,14 @@ public partial class CommandItemViewModel : ExtensionObjectViewModel, ICommandBa
         switch (propertyName)
         {
             case nameof(Command.Name):
+                // Extensions based on Command Palette SDK < 0.3 CommandItem class won't notify when Title changes because Command
+                // or Command.Name change. This is a workaround to ensure that the Title is always up-to-date for extensions with old SDK.
+                var model = _commandItemModel.Unsafe;
+                if (model != null)
+                {
+                    _itemTitle = model.Title;
+                }
+
                 UpdateProperty(nameof(Title));
                 UpdateProperty(nameof(Name));
                 break;