feat(scenic): 添加景区配置分享购买前开关

- 在AppScenicController中新增shareBeforeBuy配置返回字段
- 在ScenicConfigResp中增加shareBeforeBuy布尔类型属性
- 默认值设置为true以保持功能开启状态

src/main/java/com/ycwl/basic/model/pc/scenic/resp/ScenicConfigResp.java

@@ -55,4 +55,5 @@ public class ScenicConfigResp {
      * 视频素材包提示文案
      */
     private String videoSourcePackHint = "";
+    private Boolean shareBeforeBuy = true;
 }