refactor: Remove unused useMemo import from ObjectTable

Co-authored-by: huangyiirene <7665279+huangyiirene@users.noreply.github.com>

Author: Copilot

packages/plugin-object/src/ObjectTable.tsx

@@ -13,7 +13,7 @@
  * It integrates with ObjectQL's schema system to generate columns and handle CRUD operations.
  */
 
-import React, { useEffect, useState, useCallback, useMemo } from 'react';
+import React, { useEffect, useState, useCallback } from 'react';
 import type { ObjectTableSchema, TableColumn, TableSchema } from '@object-ui/types';
 import type { ObjectQLDataSource } from '@object-ui/data-objectql';
 import { SchemaRenderer } from '@object-ui/react';