feat: 在 dashboard 右上角添加文档链接

frontend/src/components/layout/AppHeader.vue

@@ -21,8 +21,20 @@
         </div>
       </div>
 
-      <!-- Right: Language + Subscriptions + Balance + User Dropdown -->
+      <!-- Right: Docs + Language + Subscriptions + Balance + User Dropdown -->
       <div class="flex items-center gap-3">
+        <!-- Docs Link -->
+        <a
+          v-if="docUrl"
+          :href="docUrl"
+          target="_blank"
+          rel="noopener noreferrer"
+          class="flex items-center gap-1.5 rounded-lg px-2.5 py-1.5 text-sm font-medium text-gray-600 transition-colors hover:bg-gray-100 hover:text-gray-900 dark:text-dark-400 dark:hover:bg-dark-800 dark:hover:text-white"
+        >
+          <Icon name="book" size="sm" />
+          <span class="hidden sm:inline">{{ t('nav.docs') }}</span>
+        </a>
+
         <!-- Language Switcher -->
         <LocaleSwitcher />
 
@@ -211,6 +223,7 @@ const user = computed(() => authStore.user)
 const dropdownOpen = ref(false)
 const dropdownRef = ref<HTMLElement | null>(null)
 const contactInfo = computed(() => appStore.contactInfo)
+const docUrl = computed(() => appStore.docUrl)
 
 // 只在标准模式的管理员下显示新手引导按钮
 const showOnboardingButton = computed(() => {

frontend/src/i18n/locales/en.ts

@@ -185,7 +185,8 @@ export default {
     expand: 'Expand',
     logout: 'Logout',
     github: 'GitHub',
-    mySubscriptions: 'My Subscriptions'
+    mySubscriptions: 'My Subscriptions',
+    docs: 'Docs'
   },
 
   // Auth

frontend/src/i18n/locales/zh.ts

@@ -183,7 +183,8 @@ export default {
     expand: '展开',
     logout: '退出登录',
     github: 'GitHub',
-    mySubscriptions: '我的订阅'
+    mySubscriptions: '我的订阅',
+    docs: '文档'
   },
 
   // Auth