Mouse highlighter: support a spotlight mode - inner transparent, out a backdrop (#40043)

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- [x] **Closes:** #15512 
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https://github.com/user-attachments/assets/0748c526-fcf5-4859-b832-14a413d2cad1

src/settings-ui/Settings.UI/SettingsXAML/Views/MouseUtilsPage.xaml

@@ -214,15 +214,24 @@
                         HeaderIcon="{ui:FontIcon Glyph=}"
                         IsEnabled="{x:Bind ViewModel.IsMouseHighlighterEnabled, Mode=OneWay}">
                         <tkcontrols:SettingsExpander.Items>
-                            <tkcontrols:SettingsCard x:Uid="MouseUtils_MouseHighlighter_PrimaryButtonClickColor">
+                            <tkcontrols:SettingsCard x:Uid="MouseUtils_MouseHighlighter_PrimaryButtonClickColor" IsEnabled="{x:Bind ViewModel.IsSpotlightModeEnabled, Mode=OneWay, Converter={StaticResource BoolNegationConverter}}">
                                 <controls:AlphaColorPickerButton SelectedColor="{x:Bind Path=ViewModel.MouseHighlighterLeftButtonClickColor, Mode=TwoWay}" />
                             </tkcontrols:SettingsCard>
-                            <tkcontrols:SettingsCard x:Uid="MouseUtils_MouseHighlighter_SecondaryButtonClickColor">
+                            <tkcontrols:SettingsCard x:Uid="MouseUtils_MouseHighlighter_SecondaryButtonClickColor" IsEnabled="{x:Bind ViewModel.IsSpotlightModeEnabled, Mode=OneWay, Converter={StaticResource BoolNegationConverter}}">
                                 <controls:AlphaColorPickerButton SelectedColor="{x:Bind Path=ViewModel.MouseHighlighterRightButtonClickColor, Mode=TwoWay}" />
                             </tkcontrols:SettingsCard>
                             <tkcontrols:SettingsCard x:Uid="MouseUtils_MouseHighlighter_AlwaysColor">
                                 <controls:AlphaColorPickerButton SelectedColor="{x:Bind Path=ViewModel.MouseHighlighterAlwaysColor, Mode=TwoWay}" />
                             </tkcontrols:SettingsCard>
+                            <tkcontrols:SettingsCard x:Uid="HighlightMode">
+                                <ComboBox
+                                    x:Uid="MouseUtils_MouseHighlighter_SpotlightModeType"
+                                    MinWidth="{StaticResource SettingActionControlMinWidth}"
+                                    SelectedIndex="{x:Bind ViewModel.IsSpotlightModeEnabled, Converter={StaticResource ReverseBoolToComboBoxIndexConverter}, Mode=TwoWay}">
+                                    <ComboBoxItem x:Uid="HighlightMode_Spotlight_Mode" />
+                                    <ComboBoxItem x:Uid="HighlightMode_Circle_Highlight_Mode" />
+                                </ComboBox>
+                            </tkcontrols:SettingsCard>
                             <tkcontrols:SettingsCard x:Uid="MouseUtils_MouseHighlighter_HighlightRadius">
                                 <NumberBox
                                     MinWidth="{StaticResource SettingActionControlMinWidth}"