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

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- [x] **Closes:** #15512 
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- [x] **Tests:** Added/updated and all pass
- [x] **Localization:** All end-user-facing strings can be localized
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https://github.com/user-attachments/assets/0748c526-fcf5-4859-b832-14a413d2cad1

src/settings-ui/Settings.UI/Strings/en-us/Resources.resw

@@ -5068,4 +5068,16 @@ To record a specific window, enter the hotkey with the Alt key in the opposite m
   <data name="BugReportUnderConstruction" xml:space="preserve">
     <value>Bug report package is being created</value>
   </data>
+  <data name="HighlightMode.Description" xml:space="preserve">
+    <value>Highlight the cursor or dim the screen to spotlight it</value>
+  </data>
+  <data name="HighlightMode.Header" xml:space="preserve">
+    <value>Highlight mode</value>
+  </data>
+  <data name="HighlightMode_Circle_Highlight_Mode.Content" xml:space="preserve">
+    <value>Circle highlight</value>
+  </data>
+  <data name="HighlightMode_Spotlight_Mode.Content" xml:space="preserve">
+    <value>Spotlight</value>
+  </data>
 </root>