fix: 恢复表格分页大小 localStorage 持久化

- usePersistedPageSize: 恢复 localStorage 读写，以系统配置为 fallback
- useTableLoader: handlePageSizeChange 时写入 localStorage
- Pagination.vue: handlePageSizeChange 时写入 localStorage

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/composables/usePersistedPageSize.ts

@@ -1,9 +1,29 @@
 import { getConfiguredTableDefaultPageSize, normalizeTablePageSize } from '@/utils/tablePreferences'
 
-/**
- * 读取当前系统配置的表格默认每页条数。
- * 不再使用本地持久化缓存，所有页面统一以通用表格设置为准。
- */
+const STORAGE_KEY = 'table-page-size'
+
 export function getPersistedPageSize(fallback = getConfiguredTableDefaultPageSize()): number {
+  if (typeof window !== 'undefined') {
+    try {
+      const stored = window.localStorage.getItem(STORAGE_KEY)
+      if (stored !== null) {
+        const parsed = Number(stored)
+        if (Number.isFinite(parsed)) {
+          return normalizeTablePageSize(parsed)
+        }
+      }
+    } catch (error) {
+      console.warn('Failed to read persisted page size:', error)
+    }
+  }
   return normalizeTablePageSize(getConfiguredTableDefaultPageSize() || fallback)
 }
+
+export function setPersistedPageSize(size: number): void {
+  if (typeof window === 'undefined') return
+  try {
+    window.localStorage.setItem(STORAGE_KEY, String(size))
+  } catch (error) {
+    console.warn('Failed to persist page size:', error)
+  }
+}

frontend/src/composables/useTableLoader.ts

@@ -1,7 +1,7 @@
 import { ref, reactive, onUnmounted, toRaw } from 'vue'
 import { useDebounceFn } from '@vueuse/core'
 import type { BasePaginationResponse, FetchOptions } from '@/types'
-import { getPersistedPageSize } from './usePersistedPageSize'
+import { getPersistedPageSize, setPersistedPageSize } from './usePersistedPageSize'
 
 interface PaginationState {
   page: number
@@ -88,6 +88,7 @@ export function useTableLoader<T, P extends Record<string, any>>(options: TableL
   const handlePageSizeChange = (size: number) => {
     pagination.page_size = size
     pagination.page = 1
+    setPersistedPageSize(size)
     load()
   }