feat: 新增选项操作功能并优化问卷设计页面

- 新增 OptionAction 组件用于选项操作
- 更新 BaseSelect 组件，集成 OptionAction 功能
- 优化 Paging 组件样式
- 调整 Design 页面布局和样式

src/views/Design/Index.vue

@@ -42,6 +42,8 @@ import Draggable from './components/Draggable.vue';
 import BaseSelect from './components/Questions/BaseSelect.vue';
 import ChooseQuestion from './components/ChooseQuestion.vue';
 import Paging from './components/Questions/paging/Paging.vue';
+
+const activeIndex = ref(-1);
 /**
  * 工具函数
  */