fix(i18n): fix JSON structure and add missing Chinese translations for API Settings

- Fix duplicate validation key in common section
- Fix messages section nesting (should be sibling to common, not child)
- Add missing Chinese translations:
  - providers.showDisabled/hideDisabled/showAll
  - endpoints.showDisabled/showAll
  - common.showAll

ccw/frontend/src/locales/zh/api-settings.json

@@ -129,6 +129,9 @@
     "basicInfo": "基本信息",
     "endpointSettings": "端点设置",
     "apiBaseUpdated": "基础 URL 已更新",
+    "showDisabled": "显示已禁用",
+    "hideDisabled": "隐藏已禁用",
+    "showAll": "显示全部",
     "saveError": "保存提供商失败",
     "deleteError": "删除提供商失败",
     "toggleError": "切换提供商状态失败",
@@ -174,6 +177,9 @@
     "providerBased": "基于提供商",
     "direct": "直接",
     "off": "关闭",
+    "showDisabled": "显示已禁用",
+    "showAll": "显示全部",
+    "basicInfo": "基本信息",
     "saveError": "保存端点失败",
     "deleteError": "删除端点失败",
     "toggleError": "切换端点状态失败"
@@ -336,6 +342,7 @@
     "status": "状态",
     "provider": "提供商",
     "enableThis": "启用此",
+    "showAll": "显示全部",
     "validation": {
       "nameRequired": "名称为必填项"
     }