fix: 资质页从qualifications key读取数据（与CMS后台一致）

根因：CMS后台编辑保存到site_content key='qualifications'，
但前端页面从key='about'读取，导致改了后台前端不生效。
现在前端改为从qualifications读取，CMS编辑即时生效。

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

pages/qualifications.vue

@@ -107,10 +107,19 @@
 <script setup>
 import { useOrganizationSchema, useBreadcrumbSchema } from '~/composables/useJsonLd'
 
-const { data: about } = await usePublicApi('about')
+const { data: qualData } = await usePublicApi('qualifications')
 const { data: brand } = await usePublicApi('brand')
 const { data: contact } = await usePublicApi('contact')
 
+// qualifications key 用 safetyGuarantees，前端模板用 guarantees，做一层适配
+const about = computed(() => {
+  if (!qualData.value) return null
+  return {
+    ...qualData.value,
+    guarantees: qualData.value.guarantees || qualData.value.safetyGuarantees,
+  }
+})
+
 const seo = useSEO('qualifications')
 
 useBreadcrumbSchema([