feat: add customer service chat, optimize case and homepage, fix api proxy

这一提交完成了多项功能升级与优化：
1.  新增全局浮动客服组件，集成腾讯云TRTC聊天能力并添加错误格式化工具
2.  新增图片资源并调整部分静态文件结构
3.  优化案例页面：重构筛选逻辑、新增空状态处理、添加加载更多功能
4.  优化首页布局：修复统计数字动画、调整移动端适配样式、优化轮播逻辑
5.  重构官方内容获取工具：添加缓存机制、优化媒体资源处理
6.  优化API代理配置，移除默认本地代理并新增环境变量配置
7.  新增页面数据恢复刷新逻辑，优化页面交互体验
8.  修复按钮组件冗余代码，调整头部导航移动端样式

composables/useOfficialContent.js

@@ -2,14 +2,32 @@ const ALL_LABEL = '全部'
 const LATEST_LABEL = '最新文章'
 const FALLBACK_IMAGE = '/images/lanhu/slices/home-group95-image21@2x.png'
 
+function isUsableUrl(value) {
+  const url = String(value || '').trim()
+  if (!url || url === '#') return false
+  return !/^javascript:/i.test(url)
+}
+
 function pickUrl(asset) {
-  return asset?.url || asset?.fileUrl || asset?.filePath || ''
+  return [asset?.url, asset?.fileUrl, asset?.filePath].find(isUsableUrl) || ''
 }
 
 function buildMediaMap(media = []) {
   return new Map(media.map((asset) => [asset.id, asset]))
 }
 
+function noCacheOptions(query = {}) {
+  return {
+    query: {
+      ...query,
+      _t: Date.now()
+    },
+    headers: {
+      'Cache-Control': 'no-cache'
+    }
+  }
+}
+
 function toTags(value) {
   if (Array.isArray(value)) return value.filter(Boolean)
   return String(value || '')
@@ -29,23 +47,57 @@ function bySortAndTime(left, right) {
 
 export function useOfficialContent() {
   const config = useRuntimeConfig()
-  const serverApiBase = `${String(config.officialApiProxyTarget || 'http://localhost:8080').replace(/\/$/, '')}/api`
-  const apiBase = import.meta.server ? serverApiBase : (config.public.officialApiBase || '/api')
+  const nuxtApp = useNuxtApp()
+  const apiBase = config.public.officialApiBase || '/api'
+  const siteConfigCache = useState('public-site-config-cache', () => null)
+  const siteConfigLoaded = useState('public-site-config-loaded', () => false)
 
   function fetchPublicContent(type) {
-    console.log(apiBase)
     return $fetch('/public/content', {
       baseURL: apiBase,
-      query: { type }
+      ...noCacheOptions({ type })
+    })
+  }
+
+  function fetchPublicCategories() {
+    return $fetch('/public/categories', {
+      baseURL: apiBase,
+      ...noCacheOptions()
     })
   }
 
   function fetchHomepageSections() {
-    return $fetch('/public/homepage/sections', { baseURL: apiBase })
+    return $fetch('/public/homepage/sections', {
+      baseURL: apiBase,
+      ...noCacheOptions()
+    })
   }
 
-  function fetchPublicSiteConfig() {
-    return $fetch('/public/site-config', { baseURL: apiBase })
+  function fetchPublicSiteConfig(options = {}) {
+    if (!options.fresh && siteConfigLoaded.value) return siteConfigCache.value || {}
+
+    nuxtApp._publicSiteConfigPromise ||= $fetch('/public/site-config', {
+      baseURL: apiBase,
+      ...noCacheOptions()
+    })
+      .then((rows) => {
+        siteConfigCache.value = rows || {}
+        siteConfigLoaded.value = true
+        return siteConfigCache.value
+      })
+      .finally(() => {
+        nuxtApp._publicSiteConfigPromise = null
+      })
+
+    return nuxtApp._publicSiteConfigPromise
+  }
+
+  function fetchPublicMediaAsset(id) {
+    if (!id) return null
+    return $fetch(`/public/media/${encodeURIComponent(id)}`, {
+      baseURL: apiBase,
+      ...noCacheOptions()
+    })
   }
 
   function assetUrl(assetId, mediaMap, fallback = FALLBACK_IMAGE) {
@@ -61,7 +113,8 @@ export function useOfficialContent() {
   function normalizeCase(item, mediaMap) {
     const metric = item.metricValue || ''
     const metricLabel = item.metricLabel || ''
-    const clientName = item.isAnonymous && item.clientName ? `匿名客户：${item.clientName}` : item.clientName
+    const clientName =
+      item.isAnonymous && item.clientName ? `匿名客户：${item.clientName}` : item.clientName
 
     return {
       ...item,
@@ -73,7 +126,10 @@ export function useOfficialContent() {
       description: item.description || item.summary || '',
       metric,
       metricLabel,
-      metrics: [[metric, metricLabel], [item.secondary, '辅助成果']].filter((row) => row[0]),
+      metrics: [
+        [metric, metricLabel],
+        [item.secondary, '辅助成果']
+      ].filter((row) => row[0]),
       secondary: item.secondary || '',
       contentHtml: item.contentHtml || ''
     }
@@ -104,7 +160,7 @@ export function useOfficialContent() {
       excerpt: item.summary || item.description || '',
       cta: item.cta || '获取白皮书',
       cover: item.coverUrl || assetUrl(item.coverAssetId, mediaMap),
-      documentUrl: item.documentUrl || pickUrl(documentAsset),
+      documentUrl: isUsableUrl(item.documentUrl) ? item.documentUrl : pickUrl(documentAsset),
       documentName: item.documentName || documentAsset?.name || item.title,
       contentHtml: item.contentHtml || ''
     }
@@ -120,8 +176,10 @@ export function useOfficialContent() {
     LATEST_LABEL,
     bySortAndTime,
     buildMediaMap,
+    fetchPublicCategories,
     fetchPublicContent,
     fetchHomepageSections,
+    fetchPublicMediaAsset,
     fetchPublicSiteConfig,
     normalizeCase,
     normalizeArticle,