* Add constructor Key(int) and operator for handled with non-Bmp.
* Fix TextField non-BMP issues
* Fix TextField PositionCursor.
* Reformat
* Add IsValidInput method to handle clipboard paste when pressing CTRL+V in WT
* Add handle IsValidInput in FakeDriver and unit tests
* Fixes#3984 - `Margin` w/out shadow should not force draw (#3985)
* shortcut tests
* Generic demos
* Optimize Margin to not defer draw if there's no shadow
* Fixes#4041. WSLClipboard doesn't handles well with surrogate pairs
* Avoid running Clipboard.Contents twice
* Fixes#4042. Microsoft.VisualStudio.TestPlatform.ObjectModel.TestPlatformException: Could not find testhost
* Moving tests to the parallelizable unit tests
* Remove unused folder
* Prevent warnings about not installed nuget packages
* Using Toplevel instead of Application.Top
* Cleanup code
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Co-authored-by: Tig <tig@users.noreply.github.com>
