feat(ui): Battle.Net 序列号/恢复码展示 + 热键复制确认

- dialog_bnet_info.go: 新增 Battle.Net 信息对话框，显示序列号
  和恢复码，支持一键复制恢复码
- row_menu: 新增 rowActionBnetInfo 动作，仅对 Battle.Net 条目可见
- 热键行为确认：autoType 已自动复制到剪贴板 + 键入前台窗口
- i18n: action_bnet_info / dialog_bnet_info_title / bnet_info_intro
  / hint_bnet_restore_code_secret 三语翻译

internal/i18n/locales/en.toml

@@ -582,3 +582,16 @@ other = "Launch at Windows startup"
 
 [hint_auto_start]
 other = "Adds the application to the Windows startup registry key."
+
+[action_bnet_info]
+other = "Serial & restore code..."
+
+[dialog_bnet_info_title]
+other = "Battle.Net serial & restore code"
+
+[bnet_info_intro]
+other = "Keep the restore code secret — anyone who has both the serial and the restore code can recover full account access."
+
+[hint_bnet_restore_code_secret]
+other = "Never share the restore code. It is the only way to recover this authenticator."
+