feat: 完成布局/仪表板/用户相关组件国际化与语言切换优化（TabBar/MainLayout/AppHeader、UsageTrend/ModelDistribution、User*、Common 组件、i18n/locale 增强）

web/admin-spa/src/components/layout/AppHeader.vue

@@ -60,7 +60,7 @@
             @click="userMenuOpen = !userMenuOpen"
           >
             <i class="fas fa-user-circle text-sm sm:text-base" />
-            <span class="hidden sm:inline">{{ currentUser.username || 'Admin' }}</span>
+            <span class="hidden sm:inline">{{ currentUser.username || t('common.admin') }}</span>
             <i
               class="fas fa-chevron-down ml-1 text-xs transition-transform duration-200"
               :class="{ 'rotate-180': userMenuOpen }"
@@ -191,7 +191,7 @@
             class="form-input w-full cursor-not-allowed bg-gray-100 dark:bg-gray-700 dark:text-gray-300"
             disabled
             type="text"
-            :value="currentUser.username || 'Admin'"
+            :value="currentUser.username || t('common.admin')"
           />
           <p class="mt-2 text-xs text-gray-500 dark:text-gray-400">
             {{ t('header.changePasswordModal.currentUsernameHint') }}
@@ -298,7 +298,7 @@ const authStore = useAuthStore()
 const { t } = useI18n()
 
 // 当前用户信息
-const currentUser = computed(() => authStore.user || { username: 'Admin' })
+const currentUser = computed(() => authStore.user || {})
 
 // OEM设置
 const oemSettings = computed(() => authStore.oemSettings || {})

web/admin-spa/src/components/layout/MainLayout.vue

@@ -22,10 +22,13 @@
 <script setup>
 import { ref, watch, nextTick, computed } from 'vue'
 import { useRoute, useRouter } from 'vue-router'
+import { useI18n } from 'vue-i18n'
 import { useAuthStore } from '@/stores/auth'
 import AppHeader from './AppHeader.vue'
 import TabBar from './TabBar.vue'
 
+const { t } = useI18n()
+
 const route = useRoute()
 const router = useRouter()
 const authStore = useAuthStore()
@@ -124,7 +127,7 @@ const handleTabChange = async (tabKey) => {
   } catch (err) {
     // 如果路由切换失败，恢复activeTab状态
     if (err.name !== 'NavigationDuplicated') {
-      console.error('路由切换失败:', err)
+      console.error(t('layout.mainLayout.routing.routeChangeError'), err)
       // 恢复到当前路由对应的tab
       initActiveTab()
     }

web/admin-spa/src/components/layout/TabBar.vue

@@ -38,8 +38,11 @@
 
 <script setup>
 import { computed } from 'vue'
+import { useI18n } from 'vue-i18n'
 import { useAuthStore } from '@/stores/auth'
 
+const { t } = useI18n()
+
 defineProps({
   activeTab: {
     type: String,
@@ -54,24 +57,49 @@ const authStore = useAuthStore()
 // 根据 LDAP 配置动态生成 tabs
 const tabs = computed(() => {
   const baseTabs = [
-    { key: 'dashboard', name: '仪表板', shortName: '仪表板', icon: 'fas fa-tachometer-alt' },
-    { key: 'apiKeys', name: 'API Keys', shortName: 'API', icon: 'fas fa-key' },
-    { key: 'accounts', name: '账户管理', shortName: '账户', icon: 'fas fa-user-circle' }
+    {
+      key: 'dashboard',
+      name: t('layout.tabBar.tabs.dashboard.name'),
+      shortName: t('layout.tabBar.tabs.dashboard.shortName'),
+      icon: 'fas fa-tachometer-alt'
+    },
+    {
+      key: 'apiKeys',
+      name: t('layout.tabBar.tabs.apiKeys.name'),
+      shortName: t('layout.tabBar.tabs.apiKeys.shortName'),
+      icon: 'fas fa-key'
+    },
+    {
+      key: 'accounts',
+      name: t('layout.tabBar.tabs.accounts.name'),
+      shortName: t('layout.tabBar.tabs.accounts.shortName'),
+      icon: 'fas fa-user-circle'
+    }
   ]
 
   // 只有在 LDAP 启用时才显示用户管理
   if (authStore.oemSettings?.ldapEnabled) {
     baseTabs.push({
       key: 'userManagement',
-      name: '用户管理',
-      shortName: '用户',
+      name: t('layout.tabBar.tabs.userManagement.name'),
+      shortName: t('layout.tabBar.tabs.userManagement.shortName'),
       icon: 'fas fa-users'
     })
   }
 
   baseTabs.push(
-    { key: 'tutorial', name: '使用教程', shortName: '教程', icon: 'fas fa-graduation-cap' },
-    { key: 'settings', name: '系统设置', shortName: '设置', icon: 'fas fa-cogs' }
+    {
+      key: 'tutorial',
+      name: t('layout.tabBar.tabs.tutorial.name'),
+      shortName: t('layout.tabBar.tabs.tutorial.shortName'),
+      icon: 'fas fa-graduation-cap'
+    },
+    {
+      key: 'settings',
+      name: t('layout.tabBar.tabs.settings.name'),
+      shortName: t('layout.tabBar.tabs.settings.shortName'),
+      icon: 'fas fa-cogs'
+    }
   )
 
   return baseTabs