Create CustomBanner widget for displaying banners

lib/custom_banner.dart

+import 'package:flutter/material.dart';
+
+class CustomBanner extends StatelessWidget {
+  const CustomBanner({
+    super.key,
+    required this.child,
+    required this.message,
+    this.color = Colors.red,
+    this.location = BannerLocation.topEnd,
+  });
+
+  final Widget child;
+  final String message;
+  final Color color;
+  final BannerLocation location;
+
+  @override
+  Widget build(BuildContext context) {
+    return Stack(
+      children: <Widget>[
+        child,
+        CustomPaint(
+          painter: BannerPainter(
+            textDirection: Directionality.of(context),
+            layoutDirection: Directionality.of(context),
+            location: BannerLocation.bottomEnd,
+            color: color,
+            textStyle: const TextStyle(
+              color: Colors.white,
+              fontWeight: FontWeight.bold,
+              fontSize: 12.0,
+            ),
+            message: message,
+          ),
+          child: Container(),
+        ),
+      ],
+    );
+  }
+}