feat(windows): add fabric support (#2321)

# Summary
This PR adds Fabric support and a FabricExample app for Windows.

Windows support for Fabric is experimental and as such APIs are subject
to change/break.

## Test Plan


https://github.com/software-mansion/react-native-svg/assets/1422161/2a7db119-44a8-4ee1-a837-41ca8320d8fa

## Compatibility

| OS      | Implemented |
| ------- | :---------: |
| iOS     |    ❌     |
| Android |    ❌     |
| Windows |    ✅     |

## Checklist
- [x] I have tested this on a device and a simulator
- [ ] I added documentation in `README.md`
- [ ] I updated the typed files (typescript)
- [ ] I added a test for the API in the `__tests__` folder

windows/RNSVG/LinearGradientViewManager.cpp

@@ -1,6 +1,8 @@
 #include "pch.h"
 #include "LinearGradientViewManager.h"
+#if __has_include("LinearGradientViewManager.g.cpp")
 #include "LinearGradientViewManager.g.cpp"
+#endif
 
 using namespace winrt;
 using namespace Microsoft::ReactNative;