chore(project): 初始化项目基础配置文件

- 添加 CodeGraph、Android 和通用 gitignore 配置
- 创建项目元数据文件跟踪 Flutter 项目属性
- 添加 Codex AI 指导文档 AGENTS.md 说明项目架构
- 配置代码分析选项 analysis_options.yaml
- 设置 Android 应用清单权限和 Kiosk 模式配置
- 实现中英文国际化支持 AppLocalizations
- 配置 GoRouter 应用路由导航
- 创建明亮工业控制风格的主题配置 AppTheme

lib/shared/services/toast_service.dart

@@ -0,0 +1,82 @@
+import 'package:flutter/material.dart';
+import '../../core/theme/app_theme.dart';
+
+/// Toast 服务
+/// 统一的消息提示管理
+class ToastService {
+  /// 显示成功提示
+  static void showSuccess(BuildContext context, String message) {
+    ScaffoldMessenger.of(context).showSnackBar(
+      SnackBar(
+        content: Row(
+          children: [
+            const Icon(Icons.check_circle, color: Colors.white, size: 20),
+            const SizedBox(width: 12),
+            Expanded(child: Text(message)),
+          ],
+        ),
+        backgroundColor: AppTheme.successColor,
+        duration: const Duration(seconds: 3),
+        behavior: SnackBarBehavior.floating,
+        margin: const EdgeInsets.all(16),
+      ),
+    );
+  }
+
+  /// 显示错误提示
+  static void showError(BuildContext context, String message) {
+    ScaffoldMessenger.of(context).showSnackBar(
+      SnackBar(
+        content: Row(
+          children: [
+            const Icon(Icons.error, color: Colors.white, size: 20),
+            const SizedBox(width: 12),
+            Expanded(child: Text(message)),
+          ],
+        ),
+        backgroundColor: AppTheme.errorColor,
+        duration: const Duration(seconds: 4),
+        behavior: SnackBarBehavior.floating,
+        margin: const EdgeInsets.all(16),
+      ),
+    );
+  }
+
+  /// 显示警告提示
+  static void showWarning(BuildContext context, String message) {
+    ScaffoldMessenger.of(context).showSnackBar(
+      SnackBar(
+        content: Row(
+          children: [
+            const Icon(Icons.warning, color: Colors.white, size: 20),
+            const SizedBox(width: 12),
+            Expanded(child: Text(message)),
+          ],
+        ),
+        backgroundColor: AppTheme.warningColor,
+        duration: const Duration(seconds: 3),
+        behavior: SnackBarBehavior.floating,
+        margin: const EdgeInsets.all(16),
+      ),
+    );
+  }
+
+  /// 显示信息提示
+  static void showInfo(BuildContext context, String message) {
+    ScaffoldMessenger.of(context).showSnackBar(
+      SnackBar(
+        content: Row(
+          children: [
+            const Icon(Icons.info, color: Colors.white, size: 20),
+            const SizedBox(width: 12),
+            Expanded(child: Text(message)),
+          ],
+        ),
+        backgroundColor: AppTheme.primaryColor,
+        duration: const Duration(seconds: 3),
+        behavior: SnackBarBehavior.floating,
+        margin: const EdgeInsets.all(16),
+      ),
+    );
+  }
+}