Always on top: window context menu to always on top (#45773)

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## Summary of the Pull Request

Add an option to enable inject a window context menu to always on top
this window.

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## PR Checklist

- [ ] Closes: #45638 #15387
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issues) -->
- [ ] **Communication:** I've discussed this with core contributors
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- [ ] **Tests:** Added/updated and all pass
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- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
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## Detailed Description of the Pull Request / Additional comments

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https://github.com/user-attachments/assets/37eb3f74-1ccc-42f2-83c3-1100f55765ee

---------

Co-authored-by: Niels Laute <niels.laute@live.nl>

src/settings-ui/Settings.UI.Library/AlwaysOnTopProperties.cs

@@ -12,6 +12,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
     {
         public static readonly HotkeySettings DefaultHotkeyValue = new HotkeySettings(true, true, false, false, 0x54);
         public const bool DefaultFrameEnabled = true;
+        public const bool DefaultShowInSystemMenu = false;
         public const int DefaultFrameThickness = 15;
         public const string DefaultFrameColor = "#0099cc";
         public const bool DefaultFrameAccentColor = true;
@@ -23,6 +24,7 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         public AlwaysOnTopProperties()
         {
             Hotkey = new KeyboardKeysProperty(DefaultHotkeyValue);
+            ShowInSystemMenu = new BoolProperty(DefaultShowInSystemMenu);
             FrameEnabled = new BoolProperty(DefaultFrameEnabled);
             FrameThickness = new IntProperty(DefaultFrameThickness);
             FrameColor = new StringProperty(DefaultFrameColor);
@@ -40,6 +42,9 @@ namespace Microsoft.PowerToys.Settings.UI.Library
         [JsonPropertyName("frame-enabled")]
         public BoolProperty FrameEnabled { get; set; }
 
+        [JsonPropertyName("show-in-system-menu")]
+        public BoolProperty ShowInSystemMenu { get; set; }
+
         [JsonPropertyName("frame-thickness")]
         public IntProperty FrameThickness { get; set; }