refactor(frontend): UI/UX改进和组件优化

- DataTable组件操作列自适应
- 优化各种Modal弹窗
- 统一API调用方式（AbortSignal）
- 添加全局订阅状态管理
- 优化各管理视图的交互和布局
- 修复国际化翻译问题

frontend/src/views/admin/UsageView.vue

@@ -224,7 +224,7 @@
                 v-model="filters.api_key_id"
                 :options="apiKeyOptions"
                 :placeholder="t('usage.allApiKeys')"
-                :disabled="!selectedUser && apiKeys.length === 0"
+                searchable
                 @change="applyFilters"
               />
             </div>
@@ -236,6 +236,7 @@
                 v-model="filters.model"
                 :options="modelOptions"
                 :placeholder="t('admin.usage.allModels')"
+                searchable
                 @change="applyFilters"
               />
             </div>
@@ -534,6 +535,7 @@
         :total="pagination.total"
         :page-size="pagination.page_size"
         @update:page="handlePageChange"
+        @update:pageSize="handlePageSizeChange"
       />
     </div>
   </AppLayout>
@@ -666,6 +668,7 @@ const models = ref<string[]>([])
 const accounts = ref<any[]>([])
 const groups = ref<any[]>([])
 const loading = ref(false)
+let abortController: AbortController | null = null
 
 // User search state
 const userSearchKeyword = ref('')
@@ -675,7 +678,7 @@ const showUserDropdown = ref(false)
 const selectedUser = ref<SimpleUser | null>(null)
 let searchTimeout: ReturnType<typeof setTimeout> | null = null
 
-// API Key options computed from selected user's keys
+// API Key options computed from loaded keys
 const apiKeyOptions = computed(() => {
   return [
     { value: null, label: t('usage.allApiKeys') },
@@ -796,7 +799,7 @@ const selectUser = async (user: SimpleUser) => {
   filters.value.api_key_id = undefined
 
   // Load API keys for selected user
-  await loadApiKeysForUser(user.id)
+  await loadApiKeys(user.id)
   applyFilters()
 }
 
@@ -807,10 +810,11 @@ const clearUserFilter = () => {
   filters.value.user_id = undefined
   filters.value.api_key_id = undefined
   apiKeys.value = []
+  loadApiKeys()
   applyFilters()
 }
 
-const loadApiKeysForUser = async (userId: number) => {
+const loadApiKeys = async (userId?: number) => {
   try {
     apiKeys.value = await adminAPI.usage.searchApiKeys(userId)
   } catch (error) {
@@ -863,7 +867,24 @@ const formatCacheTokens = (value: number): string => {
   return value.toLocaleString()
 }
 
+const isAbortError = (error: unknown): boolean => {
+  if (error instanceof DOMException && error.name === 'AbortError') {
+    return true
+  }
+  if (typeof error === 'object' && error !== null) {
+    const maybeError = error as { code?: string; name?: string }
+    return maybeError.code === 'ERR_CANCELED' || maybeError.name === 'CanceledError'
+  }
+  return false
+}
+
 const loadUsageLogs = async () => {
+  if (abortController) {
+    abortController.abort()
+  }
+  const controller = new AbortController()
+  abortController = controller
+  const { signal } = controller
   loading.value = true
   try {
     const params: AdminUsageQueryParams = {
@@ -872,17 +893,23 @@ const loadUsageLogs = async () => {
       ...filters.value
     }
 
-    const response = await adminAPI.usage.list(params)
+    const response = await adminAPI.usage.list(params, { signal })
+    if (signal.aborted) {
+      return
+    }
     usageLogs.value = response.items
     pagination.value.total = response.total
     pagination.value.pages = response.pages
 
-    // Extract models from loaded logs for filter options
-    extractModelsFromLogs()
   } catch (error) {
+    if (signal.aborted || isAbortError(error)) {
+      return
+    }
     appStore.showError(t('usage.failedToLoad'))
   } finally {
-    loading.value = false
+    if (!signal.aborted && abortController === controller) {
+      loading.value = false
+    }
   }
 }
 
@@ -944,27 +971,37 @@ const applyFilters = () => {
 // Load filter options
 const loadFilterOptions = async () => {
   try {
-    // Load accounts
-    const accountsResponse = await adminAPI.accounts.list(1, 1000)
+    const [accountsResponse, groupsResponse] = await Promise.all([
+      adminAPI.accounts.list(1, 1000),
+      adminAPI.groups.list(1, 1000)
+    ])
     accounts.value = accountsResponse.items || []
-
-    // Load groups
-    const groupsResponse = await adminAPI.groups.list(1, 1000)
     groups.value = groupsResponse.items || []
   } catch (error) {
     console.error('Failed to load filter options:', error)
   }
+  await loadModelOptions()
 }
 
-// Extract unique models from usage logs
-const extractModelsFromLogs = () => {
-  const uniqueModels = new Set<string>()
-  usageLogs.value.forEach(log => {
-    if (log.model) {
-      uniqueModels.add(log.model)
-    }
-  })
-  models.value = Array.from(uniqueModels).sort()
+const loadModelOptions = async () => {
+  try {
+    const endDate = new Date()
+    const startDateRange = new Date(endDate)
+    startDateRange.setDate(startDateRange.getDate() - 29)
+    const response = await adminAPI.dashboard.getModelStats({
+      start_date: startDateRange.toISOString().split('T')[0],
+      end_date: endDate.toISOString().split('T')[0]
+    })
+    const uniqueModels = new Set<string>()
+    response.models?.forEach((stat) => {
+      if (stat.model) {
+        uniqueModels.add(stat.model)
+      }
+    })
+    models.value = Array.from(uniqueModels).sort()
+  } catch (error) {
+    console.error('Failed to load model options:', error)
+  }
 }
 
 const resetFilters = () => {
@@ -987,6 +1024,7 @@ const resetFilters = () => {
   // Reset date range to default (last 7 days)
   initializeDateRange()
   pagination.value.page = 1
+  loadApiKeys()
   loadUsageLogs()
   loadUsageStats()
   loadChartData()
@@ -997,6 +1035,12 @@ const handlePageChange = (page: number) => {
   loadUsageLogs()
 }
 
+const handlePageSizeChange = (pageSize: number) => {
+  pagination.value.page_size = pageSize
+  pagination.value.page = 1
+  loadUsageLogs()
+}
+
 const exportToCSV = () => {
   if (usageLogs.value.length === 0) {
     appStore.showWarning(t('usage.noDataToExport'))
@@ -1072,6 +1116,7 @@ const hideTooltip = () => {
 onMounted(() => {
   initializeDateRange()
   loadFilterOptions()
+  loadApiKeys()
   loadUsageLogs()
   loadUsageStats()
   loadChartData()
@@ -1083,5 +1128,8 @@ onUnmounted(() => {
   if (searchTimeout) {
     clearTimeout(searchTimeout)
   }
+  if (abortController) {
+    abortController.abort()
+  }
 })
 </script>