fix: resolve 5 linter issues from CI

- main.dart: add const MyApp({super.key}) (use_key_in_widget_constructors)
- main.dart: runApp(const MyApp()) and home: const StatusAlertScreen() (prefer_const_constructors)
- main.dart: replace deprecated primarySwatch with colorScheme.fromSeed
- status_alert_base_widget.dart: use const Tween<double>(...) (prefer_const_constructors)
- status_alert_manager.dart: remove unused onComplete parameter

https://claude.ai/code/session_017nS5t2oQz1X4o359oZiRVS

Author: claude

example/lib/main.dart

@@ -1,20 +1,22 @@
 import 'package:example/screens/status_alert_screen.dart';
 import 'package:flutter/material.dart';
 
-void main() => runApp(MyApp());
+void main() => runApp(const MyApp());
 
 class MyApp extends StatelessWidget {
+  const MyApp({super.key});
+
   @override
   Widget build(BuildContext context) {
     return MaterialApp(
       debugShowCheckedModeBanner: false,
       title: 'Flutter Demo',
       theme: ThemeData(
-        primarySwatch: Colors.deepPurple,
+        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
         brightness: Brightness.light,
       ),
       darkTheme: ThemeData(brightness: Brightness.dark),
-      home: StatusAlertScreen(),
+      home: const StatusAlertScreen(),
     );
   }
 }

lib/src/status_alert.dart

@@ -44,7 +44,6 @@ class StatusAlert {
     StatusAlertManager.createView(
       context: context,
       dismissOnBackgroundTap: dismissOnBackgroundTap,
-      onComplete: onComplete,
       child: StatusAlertBaseWidget(
         title: title,
         margin: margin,

lib/src/utils/status_alert_manager.dart

@@ -10,7 +10,6 @@ class StatusAlertManager {
     required BuildContext context,
     required Widget child,
     bool dismissOnBackgroundTap = false,
-    VoidCallback? onComplete,
   }) {
     if (isVisible) return;
 

lib/src/widgets/status_alert_base_widget.dart

@@ -50,8 +50,8 @@ class _StatusAlertBaseWidgetState extends State<StatusAlertBaseWidget>
   late final Animation<double> _scaleAnimation;
   late final Animation<double> _fadeAnimation;
 
-  final Tween<double> _scaleTween = Tween<double>(begin: 0.9, end: 1.0);
-  final Tween<double> _fadeTween = Tween<double>(begin: 0.0, end: 1.0);
+  final Tween<double> _scaleTween = const Tween<double>(begin: 0.9, end: 1.0);
+  final Tween<double> _fadeTween = const Tween<double>(begin: 0.0, end: 1.0);
 
   @override
   void initState() {