refactor(saleFlowProImprove): 优化受益人和被保人信息处理逻辑

- 将受益人信息保存任务改为异步调用
- 使用严格相等运算符替换松散比较
- 删除空媒体数据字段以避免无效提交

src/views/ebiz/saleFlowProImprove/Beneficiary.vue

@@ -284,8 +284,8 @@ export default {
       const taskID = 'saveBeneficiary'
       this.nextStepProcesserContainer.registerMainTask(
         taskID,
-        () => {
-          return this.nextStep()
+        async () => {
+          return await this.nextStep()
         },
         this.preTasks
       )

src/views/ebiz/saleFlowProImprove/InsuredPerson.vue

@@ -1801,7 +1801,7 @@ export default {
           }
         }
       }
-      if (this.userInfo.mediaDTOS == '') {
+      if (this.userInfo.mediaDTOS === '') {
         delete this.userInfo.mediaDTOS
       }
       params.orderDTO.insuredDTOs = [this.userInfo]