Migrate NativeViewHierarchyManager from Java to Kotlin

Summary:
Mechanical migration of the deprecated `NativeViewHierarchyManager` stub class from Java to Kotlin. All methods remain empty stubs — no behavioral changes.

Key migration decisions:
- Class marked `open` to preserve subclassability from Java/Kotlin
- All non-final public/protected methods marked `open` to match Java virtual-by-default
- `resolveView` and `resolveViewManager` remain `final` (matching the Java original)
- `Nullable` return types converted to Kotlin nullable types (`?`)
- `synchronized` methods use `Synchronized` annotation
- Static initializer converted to companion object `init` block

Changelog:
[Internal]

Differential Revision: D104999732

Author: cortinico

packages/react-native/ReactAndroid/api/ReactAndroid.api

@@ -3461,6 +3461,7 @@ public final class com/facebook/react/uimanager/MeasureSpecAssertions {
 }
 
 public class com/facebook/react/uimanager/NativeViewHierarchyManager {
+	public static final field Companion Lcom/facebook/react/uimanager/NativeViewHierarchyManager$Companion;
 	public fun <init> (Lcom/facebook/react/uimanager/ViewManagerRegistry;)V
 	public fun <init> (Lcom/facebook/react/uimanager/ViewManagerRegistry;Lcom/facebook/react/uimanager/RootViewManager;)V
 	public fun addRootView (ILandroid/view/View;)V
@@ -3490,6 +3491,9 @@ public class com/facebook/react/uimanager/NativeViewHierarchyManager {
 	public fun updateViewExtraData (ILjava/lang/Object;)V
 }
 
+public final class com/facebook/react/uimanager/NativeViewHierarchyManager$Companion {
+}
+
 public final class com/facebook/react/uimanager/NativeViewHierarchyOptimizer {
 	public fun <init> ()V
 }