fix: render SVG on macOS Fabric by opting out of updateLayer

[gabrieldonadel]

Summary

Fixes SVG not rendering on macOS when the new arch is enabled. On macOS Fabric, RNSVGSvgView inherits from RCTViewComponentView, which returns YES for -wantsUpdateLayer. When wantsUpdateLayer is YES, AppKit calls -updateLayer to set the layer's contents and skips -drawRect: entirely. Since RNSVGSvgView renders all of its SVG content inside -drawRect: (via drawToContext:withRect:), nothing was being painted on macOS new arch — the view stayed blank.

Test Plan

Verified that SVGs render correctly on a macOS app with RCT_NEW_ARCH_ENABLED=1. Without the fix the view paints nothing; with the fix drawRect: is called and SVG content is drawn as expected.

1. Build and run the react-native-svg example app on macOS with the New Architecture enabled.
2. Open any screen that renders an <Svg> (e.g. the basic shapes example).
3. Before this PR: the SVG area is blank.
4. After this PR: the SVG renders correctly, identical to the old-arch behavior.

Compatibility

OS	Implemented
iOS	N/A
MacOS	✅
Android	N/A
Web	N/A

Checklist

• 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