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/RedeemView.vue

@@ -186,6 +186,7 @@
           :total="pagination.total"
           :page-size="pagination.page_size"
           @update:page="handlePageChange"
+          @update:pageSize="handlePageSizeChange"
         />
 
         <!-- Batch Actions -->
@@ -542,6 +543,8 @@ const pagination = reactive({
   pages: 0
 })
 
+let abortController: AbortController | null = null
+
 const showDeleteDialog = ref(false)
 const showDeleteUnusedDialog = ref(false)
 const deletingCode = ref<RedeemCode | null>(null)
@@ -556,21 +559,46 @@ const generateForm = reactive({
 })
 
 const loadCodes = async () => {
+  if (abortController) {
+    abortController.abort()
+  }
+  const currentController = new AbortController()
+  abortController = currentController
   loading.value = true
   try {
-    const response = await adminAPI.redeem.list(pagination.page, pagination.page_size, {
-      type: filters.type as RedeemCodeType,
-      status: filters.status as any,
-      search: searchQuery.value || undefined
-    })
+    const response = await adminAPI.redeem.list(
+      pagination.page,
+      pagination.page_size,
+      {
+        type: filters.type as RedeemCodeType,
+        status: filters.status as any,
+        search: searchQuery.value || undefined
+      },
+      {
+        signal: currentController.signal
+      }
+    )
+    if (currentController.signal.aborted) {
+      return
+    }
     codes.value = response.items
     pagination.total = response.total
     pagination.pages = response.pages
-  } catch (error) {
+  } catch (error: any) {
+    if (
+      currentController.signal.aborted ||
+      error?.name === 'AbortError' ||
+      error?.code === 'ERR_CANCELED'
+    ) {
+      return
+    }
     appStore.showError(t('admin.redeem.failedToLoad'))
     console.error('Error loading redeem codes:', error)
   } finally {
-    loading.value = false
+    if (abortController === currentController && !currentController.signal.aborted) {
+      loading.value = false
+      abortController = null
+    }
   }
 }
 
@@ -588,6 +616,12 @@ const handlePageChange = (page: number) => {
   loadCodes()
 }
 
+const handlePageSizeChange = (pageSize: number) => {
+  pagination.page_size = pageSize
+  pagination.page = 1
+  loadCodes()
+}
+
 const handleGenerateCodes = async () => {
   // 订阅类型必须选择分组
   if (generateForm.type === 'subscription' && !generateForm.group_id) {