[Enhancement] Support ShadowEffect on UWP

[YZahringer]

Summary

Support ShadowEffect on UWP platform. Currently only supported by Android/iOS/macOS on #725.

API Changes

No API change, add UWP implementation of ShadowEffect. Maybe using DropShadow.

Intended Use Case

Use ShadowEffect on UWP platform.

Who Will Do The Work?

• I am willing to take this on myself
• Just putting this out there for someone to pick up

[jfversluis]

We already have this for other platforms, we definitely need this for UWP

[MichaelStgt]

Have a look at the Windows Community Toolkit. They have a shadow for windows UWP and I implemented it in my Controls Toolbox, but only in a Custom Frame Control.

[sattew]

Have a look at the Windows Community Toolkit. They have a shadow for windows UWP and I implemented it in my Controls Toolbox, but only in a Custom Frame Control.

Did you mean this shadow?

[TheCodeTraveler]

Fixed in #1102