allDartFiles method
Returns a list of all .dart files found recursively in the given
directory.
Only includes files that end with the .dart extensi
Implementation
List<File> allDartFiles(Directory directory) {
final dartFiles = directory
.listSync(recursive: true)
.whereType<File>()
.where((f) => f.path.endsWith('.dart'));
return dartFiles.toList();
}