Adds a video trim dialog to ZoomIt (#45334)

## Summary of the Pull Request
Adds a video trim dialog to ZoomIt

## PR Checklist
Closes 45333

## Validation Steps Performed
Manual validation

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Co-authored-by: Mark Russinovich <markruss@ntdev.microsoft.com>
Co-authored-by: foxmsft <foxmsft@hotmail.com>

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

@@ -89,6 +89,8 @@ namespace Microsoft.PowerToys.Settings.UI.Library
 
         public StringProperty RecordFormat { get; set; }
 
+        public BoolProperty CaptureSystemAudio { get; set; }
+
         public BoolProperty CaptureAudio { get; set; }
 
         public StringProperty MicrophoneDeviceId { get; set; }