Cesium for Unreal v2.19.0

This release includes support for Unreal Engine v5.4, v5.5, and v5.6 for Windows, Linux, macOS, Android, and iOS. Please select the appropriate ZIP for your version.

• Unreal Engine 5.4: CesiumForUnreal-54-v2.19.0.zip
• Unreal Engine 5.5: CesiumForUnreal-55-v2.19.0.zip
• Unreal Engine 5.6: CesiumForUnreal-56-v2.19.0.zip

Additions 🎉

• Added assets for the IAU2015 Moon and Mars ellipsoids under Content.

Fixes 🔧

• Added a missing CesiumRuntime.h include in CesiumPropertyAttribute.cpp that broke compilation in v2.18.0 on Windows.
• Fixed a bug in FCesiumVectorStyle that made polygons use the color mode from LineStyle instead of PolygonStyle.
• Fixed a bug that could cause a crash when undoing and redoing deletion of a CesiumRasterOverlay component.
• Fixed a crash in UCesiumLoadGeoJsonDocumentFromIonAsyncAction that occurred when a Cesium ion server was not specified. The action will now fall back to the default ion server, similar to ACesium3DTileset.

In addition to the above, this release updates cesium-native from v0.50.0 to v0.51.0. See the changelog for a complete list of changes in cesium-native.