hookDeclaresCodeAsset function
True if hook/build.dart declares a CodeAsset — generated OR hand-written
(e.g. nitro_server's prebuilt downloader). Such a hook delivers the library,
so a platform that also builds the engine double-bundles.
Implementation
bool hookDeclaresCodeAsset(String baseDir) {
final f = File(p.join(baseDir, 'hook', 'build.dart'));
if (!f.existsSync()) return false;
final s = f.readAsStringSync();
return s.contains('CodeAsset(') || s.contains('assets.code.add');
}