Remove redundant feature flag overrides (#56014)

Summary:
Pull Request resolved: #56014

Changelog: [internal]

Clean up React Native feature flag override classes by removing overrides that return values identical to their parent class defaults:

- **ReactNativeNewArchitectureFeatureFlagsDefaults**: Removed unnecessary `newArchitectureEnabled` constant and simplified method returns to direct `true` values
- **ReactNativeFeatureFlagsOverrides_RNOSS_Stable_Android**: Removed redundant `useFabricInterop()` override (default is already `true`)

These changes improve code maintainability by eliminating unnecessary duplication without any behavioral impact.

Reviewed By: huntie

Differential Revision: D95852632

fbshipit-source-id: 89cb210210911d646ff2a2ea5bac6861730cf978

Author: rubennorte

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsOverrides_RNOSS_Stable_Android.kt

@@ -8,7 +8,4 @@
 package com.facebook.react.internal.featureflags
 
 public class ReactNativeFeatureFlagsOverrides_RNOSS_Stable_Android() :
-    ReactNativeNewArchitectureFeatureFlagsDefaults() {
-
-  override fun useFabricInterop(): Boolean = true
-}
+    ReactNativeNewArchitectureFeatureFlagsDefaults()

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeNewArchitectureFeatureFlagsDefaults.kt

@@ -23,17 +23,13 @@ package com.facebook.react.internal.featureflags
 public open class ReactNativeNewArchitectureFeatureFlagsDefaults() :
     ReactNativeFeatureFlagsDefaults() {
 
-  private val newArchitectureEnabled: Boolean = true
+  override fun enableBridgelessArchitecture(): Boolean = true
 
-  override fun enableBridgelessArchitecture(): Boolean = newArchitectureEnabled
+  override fun enableFabricRenderer(): Boolean = true
 
-  override fun enableFabricRenderer(): Boolean = newArchitectureEnabled
+  override fun useNativeViewConfigsInBridgelessMode(): Boolean = true
 
-  override fun useNativeViewConfigsInBridgelessMode(): Boolean =
-      newArchitectureEnabled || super.useNativeViewConfigsInBridgelessMode()
+  override fun useTurboModuleInterop(): Boolean = true
 
-  override fun useTurboModuleInterop(): Boolean =
-      newArchitectureEnabled || super.useTurboModuleInterop()
-
-  override fun useTurboModules(): Boolean = newArchitectureEnabled
+  override fun useTurboModules(): Boolean = true
 }