Migrate RNTester to use {usesCleartextTraffic} Manifest Placeholder (#52620)

Summary:
This creates a `debugOptimized` build type for React Native Android, meaning that we can run C++ optimization on the debug build, while still having the debugger enabled. This is aimed at improving the developer experience for folks developing on low-end devices or emulators.

Users that intend to debug can still use the `debug` variant where the full debug symbols are shipped.

## Changelog:

[ANDROID] [ADDED] - Create a debugOptimized buildType for Android

Pull Request resolved: #52620

Test Plan:
Tested locally with RNTester by doing:

```
./gradlew installDebugOptimized
```

This is the output of the 3 generated .aar. The size difference is a proof that we're correctly stripping out the C++ debug symbols:

<img width="193" height="54" alt="Screenshot 2025-07-15 at 17 49 50" src="https://github.com/user-attachments/assets/584a0e8d-2d17-40d4-ac29-da09049d6554" />
<img width="235" height="51" alt="Screenshot 2025-07-15 at 17 49 39" src="https://github.com/user-attachments/assets/eda8f9e7-3509-4334-8c16-990e55caa04d" />
<img width="184" height="52" alt="Screenshot 2025-07-15 at 17 49 32" src="https://github.com/user-attachments/assets/a5c94385-bc00-4484-b43e-088ee039827f" />

Differential Revision: D78351347

Reviewed By: cipolleschi

Pulled By: cipolleschi

Author: cortinico

packages/gradle-plugin/react-native-gradle-plugin/src/main/kotlin/com/facebook/react/ReactPlugin.kt

@@ -18,6 +18,7 @@ import com.facebook.react.tasks.GenerateEntryPointTask
 import com.facebook.react.tasks.GeneratePackageListTask
 import com.facebook.react.utils.AgpConfiguratorUtils.configureBuildConfigFieldsForApp
 import com.facebook.react.utils.AgpConfiguratorUtils.configureBuildConfigFieldsForLibraries
+import com.facebook.react.utils.AgpConfiguratorUtils.configureBuildTypesForApp
 import com.facebook.react.utils.AgpConfiguratorUtils.configureDevServerLocation
 import com.facebook.react.utils.AgpConfiguratorUtils.configureNamespaceForLibraries
 import com.facebook.react.utils.BackwardCompatUtils.configureBackwardCompatibilityReactMap
@@ -84,6 +85,7 @@ class ReactPlugin : Plugin<Project> {
       configureAutolinking(project, extension)
       configureCodegen(project, extension, rootExtension, isLibrary = false)
       configureResources(project, extension)
+      configureBuildTypesForApp(project)
     }
 
     // Library Only Configuration

packages/gradle-plugin/react-native-gradle-plugin/src/main/kotlin/com/facebook/react/utils/AgpConfiguratorUtils.kt

@@ -19,6 +19,7 @@ import java.net.Inet4Address
 import java.net.NetworkInterface
 import javax.xml.parsers.DocumentBuilder
 import javax.xml.parsers.DocumentBuilderFactory
+import kotlin.plus
 import org.gradle.api.Action
 import org.gradle.api.Project
 import org.gradle.api.plugins.AppliedPlugin
@@ -27,6 +28,26 @@ import org.w3c.dom.Element
 @Suppress("UnstableApiUsage")
 internal object AgpConfiguratorUtils {
 
+  fun configureBuildTypesForApp(project: Project) {
+    val action =
+        Action<AppliedPlugin> {
+          project.extensions
+              .getByType(ApplicationAndroidComponentsExtension::class.java)
+              .finalizeDsl { ext ->
+                ext.buildTypes {
+                  val debug =
+                      getByName("debug").apply {
+                        manifestPlaceholders["usesCleartextTraffic"] = "true"
+                      }
+                  getByName("release").apply {
+                    manifestPlaceholders["usesCleartextTraffic"] = "false"
+                  }
+                }
+              }
+        }
+    project.pluginManager.withPlugin("com.android.application", action)
+  }
+
   fun configureBuildConfigFieldsForApp(project: Project, extension: ReactExtension) {
     val action =
         Action<AppliedPlugin> {

packages/rn-tester/android/app/src/debug/AndroidManifest.xml

@@ -50,6 +50,7 @@
     </queries>
 
     <application
+        android:usesCleartextTraffic="${usesCleartextTraffic}"
         android:name=".RNTesterApplication"
         android:allowBackup="true"
         android:banner="@drawable/tv_banner"