feat(i18n): 完成全量 UI 文本国际化，替换所有硬编码中文为 AppLocalizations 调用

- core/localization: 新增约 60 个翻译键（含参数化方法），中英双语覆盖
- shared/widgets: CommonDialog 默认参数国际化
- features/home: 完成页操作步骤指引、状态栏串口连接状态、程序列表状态标签
- features/programs: 表头状态列、表单验证提示、导入/模板操作反馈、删除确认（参数化）
- features/program_detail: 步骤列表/表单标题、删除确认、速度档位显示（参数化）
- features/device: run_state_provider 错误消息改为错误码
- features/settings: 升级页、密码面板、语言面板、U盘导入面板、串口配置面板全部替换

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

lib/shared/widgets/common_dialog.dart

@@ -7,8 +7,8 @@ class CommonDialog {
     required BuildContext context,
     required String title,
     required String content,
-    String confirmText = '确认',
-    String cancelText = '取消',
+    String confirmText = 'Confirm',
+    String cancelText = 'Cancel',
     bool isDestructive = false,
   }) {
     return showDialog<bool>(
@@ -38,7 +38,7 @@ class CommonDialog {
     required BuildContext context,
     required String title,
     required String content,
-    String confirmText = '确认',
+    String confirmText = 'Confirm',
   }) {
     return showDialog(
       context: context,
@@ -61,8 +61,8 @@ class CommonDialog {
     required String title,
     String? hintText,
     String? initialValue,
-    String confirmText = '确认',
-    String cancelText = '取消',
+    String confirmText = 'Confirm',
+    String cancelText = 'Cancel',
   }) {
     final controller = TextEditingController(text: initialValue);