Add E2E tests for internationalization across multiple pages

- Implemented navigation.spec.ts to test language switching and translation of navigation elements.
- Created sessions-page.spec.ts to verify translations on the sessions page, including headers, status badges, and date formatting.
- Developed settings-page.spec.ts to ensure settings page content is translated and persists across sessions.
- Added skills-page.spec.ts to validate translations for skill categories, action buttons, and empty states.

ccw/frontend/src/locales/zh/history.json

@@ -0,0 +1,29 @@
+{
+  "title": "CLI 执行历史",
+  "description": "查看和管理 CLI 执行历史",
+  "searchPlaceholder": "搜索执行记录...",
+  "filterAllTools": "全部工具",
+  "deleteOptions": "删除选项",
+  "deleteBy": "按工具删除",
+  "deleteAllTool": "删除所有 {tool}",
+  "deleteAll": "删除全部历史",
+  "actions": {
+    "view": "查看详情",
+    "delete": "删除",
+    "copyId": "复制 ID",
+    "copied": "已复制！"
+  },
+  "dialog": {
+    "deleteTitle": "确认删除",
+    "deleteAllTitle": "删除全部历史",
+    "deleteMessage": "确定要删除此执行记录吗？此操作无法撤销。",
+    "deleteToolMessage": "确定要删除所有 {tool} 执行记录吗？此操作无法撤销。",
+    "deleteAllMessage": "确定要删除全部执行历史吗？此操作无法撤销。"
+  },
+  "empty": {
+    "title": "未找到执行记录",
+    "message": "运行 CLI 命令后，执行历史将显示在这里。",
+    "filtered": "没有匹配结果",
+    "filteredMessage": "没有匹配当前筛选条件的执行记录。请尝试调整搜索或筛选条件。"
+  }
+}