fix: Allow viewRegistry to accept subclasses of NSView

[Saadnajmi]

Summary:

In React Native macOS, we have two "shim" classes to help make the iOS codebase of React Native compatible with macOS

• RCTPlatformView:a typedef of NSView on macOS, and UIView on iOS / visionOS)
• RCTUIView: A subclass of NSView with extra methods and properties to be closer to the iOS UIView

Additionally, in React Native's old architecture, there is this line that we forked as follows in 0.73 and earlier versions:

React Native:

typedef void (^RCTViewManagerUIBlock)(RCTUIManager *uiManager, NSDictionary<NSNumber *, UIView *> *viewRegistry);

React Native macOS:

typedef void (^RCTViewManagerUIBlock)(RCTUIManager *uiManager, NSDictionary<NSNumber ,
RCTUIView> *viewRegistry); // [macOS]`

In React Native macOS 0.74+, I changed the definition as follows, thinking the widening of scope to a superclass would be a non breaking change:

typedef void (^RCTViewManagerUIBlock)(RCTUIManager *uiManager, NSDictionary<NSNumber ,
RCTPlatformView> *viewRegistry); // [macOS]`

Turns out I was wrong, and this broke libraries like Reanimated and React Native Gesture Handler. The fix is simple, add a __kindof in front of the type!

typedef void (^RCTViewManagerUIBlock)(RCTUIManager *uiManager, NSDictionary<NSNumber ,
__kindof RCTPlatformView> *viewRegistry); // [macOS]`

Test Plan:

Tested this in my branch where I'm adding macOS support to react-native-webgpu (wcandillon/react-native-webgpu#123), and reanimated + gesture gesture handler compile successfully.