🛠 Refactor: Split RNIObjectMetadata

Summary: Extract extension in `RNIObjectMetadata` into its own file.

ios/src_library/React Native/RNIObjectMetadata/RNIObjectMetadata+Default.swift

@@ -0,0 +1,29 @@
+//
+//  RNIObjectMetadata+Default.swift
+//  react-native-ios-modal
+//
+//  Created by Dominic Go on 4/27/23.
+//
+
+import Foundation
+
+fileprivate let RNIObjectMetadataMap = NSMapTable<AnyObject, AnyObject>(
+  keyOptions: .weakMemory,
+  valueOptions: .strongMemory
+);
+
+public extension RNIObjectMetadata {
+  var metadata: T? {
+    set {
+      if let newValue = newValue {
+        RNIObjectMetadataMap.setObject(newValue, forKey: self);
+
+      } else {
+        RNIObjectMetadataMap.removeObject(forKey: self);
+      };
+    }
+    get {
+      RNIObjectMetadataMap.object(forKey: self) as? T
+    }
+  };
+};

ios/src_library/React Native/RNIObjectMetadata/RNIObjectMetadata.swift

@@ -7,29 +7,8 @@
 
 import Foundation
 
-fileprivate let RNIObjectMetadataMap = NSMapTable<AnyObject, AnyObject>(
-  keyOptions: .weakMemory,
-  valueOptions: .strongMemory
-);
-
 public protocol RNIObjectMetadata: AnyObject {
   associatedtype T: AnyObject;
 
   var metadata: T? { get set };
 };
-
-public extension RNIObjectMetadata {
-  var metadata: T? {
-    set {
-      if let newValue = newValue {
-        RNIObjectMetadataMap.setObject(newValue, forKey: self);
-
-      } else {
-        RNIObjectMetadataMap.removeObject(forKey: self);
-      };
-    }
-    get {
-      RNIObjectMetadataMap.object(forKey: self) as? T
-    }
-  };
-};