resolvePath static method
Returns the path to the app-level Gradle file under projectRoot.
Checks build.gradle.kts (Kotlin DSL, RN 0.77+) first, then falls back
to build.gradle (Groovy). Returns null if neither exists.
Implementation
static String? resolvePath(String projectRoot) {
final kts = p.join(projectRoot, 'android', 'app', 'build.gradle.kts');
final groovy = p.join(projectRoot, 'android', 'app', 'build.gradle');
if (File(kts).existsSync()) return kts;
if (File(groovy).existsSync()) return groovy;
return null;
}