How to draw Arc?

arc.dart

import 'package:flutter/material.dart';

const Color darkBlue = Color.fromARGB(255, 18, 32, 47);

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData.dark().copyWith(
        scaffoldBackgroundColor: darkBlue,
      ),
      debugShowCheckedModeBanner: false,
      home: Scaffold(
        body: Center(
          child: MyWidget(),
        ),
      ),
    );
  }
}

class MyWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Stack(
      alignment: Alignment.bottomRight,
      children: [
        const CircleAvatar(
          radius: 128,
          backgroundColor: Colors.blue,
        ),
        SizedBox(
          height: 256,
          width: 256,
          child: CustomPaint(
            painter: ArcPainter(),
            child: Container(),
          ),
        ),
      ],
    );
  }
}

class ArcPainter extends CustomPainter {
  @override
  void paint(Canvas canvas, Size size) {
    var paint = Paint()
      ..color = Colors.yellow
      ..strokeWidth = 3
      ..style = PaintingStyle.fill;

    final path = Path();
    path
      ..moveTo((size.width / 2.8), size.height * .15)
      ..arcToPoint(
        Offset(size.width / 4, size.height * .85),
        clockwise: true,
        largeArc: false,
        radius: const Radius.circular(20),
      )
      ..arcToPoint(
        Offset(size.width / 4.8, size.height * .15),
        clockwise: false,
        largeArc: false,
        radius: const Radius.circular(20),
      );

    canvas.drawPath(path, paint);
  }

  @override
  bool shouldRepaint(covariant CustomPainter oldDelegate) {
    return true;
  }
}