refactor: enhance Android build configuration for new architecture support

Author: lposen

android/build.gradle

@@ -1,24 +1,20 @@
 buildscript {
-  // Buildscript is evaluated before everything else so we can't use getExtOrDefault
-  def kotlin_version = rootProject.ext.has("kotlinVersion") ? rootProject.ext.get("kotlinVersion") : project.properties["RNIterable_kotlinVersion"]
+  ext.getExtOrDefault = {name ->
+    return rootProject.ext.has(name) ? rootProject.ext.get(name) : project.properties['RNIterable_' + name]
+  }
 
   repositories {
     google()
     mavenCentral()
   }
 
   dependencies {
-    classpath "com.android.tools.build:gradle:7.2.1"
+    classpath "com.android.tools.build:gradle:8.7.2"
     // noinspection DifferentKotlinGradleVersion
-    classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+    classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:${getExtOrDefault('kotlinVersion')}"
   }
 }
 
-def reactNativeArchitectures() {
-  def value = rootProject.getProperties().get("reactNativeArchitectures")
-  return value ? value.split(",") : ["armeabi-v7a", "x86", "x86_64", "arm64-v8a"]
-}
-
 def isNewArchitectureEnabled() {
   return rootProject.hasProperty("newArchEnabled") && rootProject.getProperty("newArchEnabled") == "true"
 }
@@ -63,7 +59,11 @@ android {
   defaultConfig {
     minSdkVersion getExtOrIntegerDefault("minSdkVersion")
     targetSdkVersion getExtOrIntegerDefault("targetSdkVersion")
+    buildConfigField("boolean", "IS_NEW_ARCHITECTURE_ENABLED", isNewArchitectureEnabled().toString())
+  }
 
+  buildFeatures {
+    buildConfig true
   }
 
   buildTypes {
@@ -80,6 +80,16 @@ android {
     sourceCompatibility JavaVersion.VERSION_1_8
     targetCompatibility JavaVersion.VERSION_1_8
   }
+
+  sourceSets {
+    main {
+      if (isNewArchitectureEnabled()) {
+        java.srcDirs += ['src/newarch']
+      } else {
+        java.srcDirs += ['src/oldarch']
+      }
+    }
+  }
 }
 
 repositories {
@@ -90,10 +100,7 @@ repositories {
 def kotlin_version = getExtOrDefault("kotlinVersion")
 
 dependencies {
-  // For < 0.71, this will be from the local maven repo
-  // For > 0.71, this will be replaced by `com.facebook.react:react-android:$version` by react gradle plugin
-  //noinspection GradleDynamicVersion
-  implementation "com.facebook.react:react-native:+"
+  implementation "com.facebook.react:react-android"
   implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
   api "com.iterable:iterableapi:3.5.2"
     // api project(":iterableapi") // links to local android SDK repo rather than by release