fix: enhance pagination settings across multiple pages with default size and options

apps/admin/src/pages/TeacherWorkspace/index.tsx

@@ -146,7 +146,12 @@ const TeacherWorkspacePage: React.FC = () => {
                 columns={classColumns}
                 dataSource={data.assignedClasses}
                 rowKey="classId"
-                pagination={{ pageSize: 20, showTotal: (total) => `共 ${total} 个班级` }}
+                pagination={{
+                  defaultPageSize: 20,
+                  showSizeChanger: true,
+                  pageSizeOptions: [20, 50, 100],
+                  showTotal: (total) => `共 ${total} 个班级`,
+                }}
               />
             ) : (
               <Empty description="暂无分配的班级" />
@@ -160,7 +165,12 @@ const TeacherWorkspacePage: React.FC = () => {
                 columns={scheduleColumns}
                 dataSource={data.todaySchedules}
                 rowKey="id"
-                pagination={{ pageSize: 20, showTotal: (total) => `共 ${total} 节` }}
+                pagination={{
+                  defaultPageSize: 20,
+                  showSizeChanger: true,
+                  pageSizeOptions: [20, 50, 100],
+                  showTotal: (total) => `共 ${total} 节`,
+                }}
               />
             ) : (
               <Empty description="今日无排课" />
@@ -174,7 +184,12 @@ const TeacherWorkspacePage: React.FC = () => {
                 columns={studentColumns}
                 dataSource={data.myStudents}
                 rowKey="studentId"
-                pagination={{ pageSize: 20, showTotal: (total) => `共 ${total} 人` }}
+                pagination={{
+                  defaultPageSize: 20,
+                  showSizeChanger: true,
+                  pageSizeOptions: [20, 50, 100],
+                  showTotal: (total) => `共 ${total} 人`,
+                }}
               />
             ) : (
               <Empty description="暂无学生" />