Added a method capitalizeAllWord to make the initial word of a text capital.

class CapitalizeWords extends StatelessWidget {
  const CapitalizeWords({Key? key}) : super(key: key);

  IsCapitalize isCapitalize = IsCapitalize();
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: Text(isCapitalize.capitalizeAllWord("hello world")),
      ),
    );
  }
}