BUG修复，返回结构统一

client/src/pages/admin/EmailSuffixes.vue

@@ -78,7 +78,8 @@ const fetchSuffixes = async () => {
       headers: getAuthHeaders()
     })
     if (response.ok) {
-      suffixes.value = await response.json()
+      const data = await response.json()
+      suffixes.value = data.result || []
     }
   } catch (error) {
     console.error('Failed to fetch suffixes:', error)
@@ -108,7 +109,8 @@ const handleAdd = async () => {
       newSortOrder.value = 0
       fetchSuffixes()
     } else {
-      toast.error('添加失败')
+      const errorData = await response.json()
+      toast.error(errorData.message || '添加失败')
     }
   } catch (error) {
     console.error(error)
@@ -129,7 +131,8 @@ const handleDelete = async (id: number) => {
       toast.success('删除成功')
       fetchSuffixes()
     } else {
-      toast.error('删除失败')
+      const errorData = await response.json()
+      toast.error(errorData.message || '删除失败')
     }
   } catch (error) {
     console.error(error)