fix: Use property accessors on Frame (#2400)

* fix: Use property accessors on `Frame`

* Format

* Use `_Nonnull`

* fix: Assume nonnull

* Use `NS_ASSUME_NONNULL_BEGIN` more

* Format C++

package/ios/Frame Processor/FrameProcessorPlugin.h

@@ -12,6 +12,8 @@
 #import "VisionCameraProxy.h"
 #import <Foundation/Foundation.h>
 
+NS_ASSUME_NONNULL_BEGIN
+
 /**
  * The base class of a native Frame Processor Plugin.
  *
@@ -32,7 +34,7 @@
  *   - proxy: The VisionCameraProxy instance for using the Frame Processor Context, e.g. to initialize SharedArrays.
  *   - options: An options dictionary passed from the JS side, or `nil` if none.
  */
-- (instancetype _Nonnull)initWithProxy:(VisionCameraProxyHolder* _Nonnull)proxy
+- (instancetype _Nonnull)initWithProxy:(VisionCameraProxyHolder*)proxy
                            withOptions:(NSDictionary* _Nullable)options NS_SWIFT_NAME(init(proxy:options:));
 
 - (instancetype _Nonnull)init NS_UNAVAILABLE;
@@ -44,14 +46,17 @@
  *
  * - Parameters:
  *   - frame: The Frame from the Camera. Don't do any ref-counting on this, as VisionCamera handles that.
+ *   - arguments: An options dictionary passed from the JS side, or `nil` if none.
  * - Returns: You can return any primitive, map or array you want.
  *            See the <a href="https://react-native-vision-camera.com/docs/guides/frame-processors-plugins-overview#types">Types</a>
  *            table for a list of supported types.
  */
-- (id _Nullable)callback:(Frame* _Nonnull)frame withArguments:(NSDictionary* _Nullable)arguments;
+- (id _Nullable)callback:(Frame*)frame withArguments:(NSDictionary* _Nullable)arguments;
 
 @end
 
+NS_ASSUME_NONNULL_END
+
 #define VISION_CONCAT2(A, B) A##B
 #define VISION_CONCAT(A, B) VISION_CONCAT2(A, B)