[BUG]java对象存在map套map且内层map是同一个对象，序列化结果带ref，反序列化失败

### 问题描述
如下代码，对象map套map，内层的reversePriceMap在多个外层对象中是同一个对象，序列化出来的字符串带有ref，但是在反序列化的时候失败。在fastjson中是直接抛异常，在fastjson2中是反序列化出来的内层对象是null

### 环境信息
*请填写以下信息：*

- OS信息： macos arm
- JDK信息： 1.8
- 版本信息：2.0.57

### 重现步骤
*如何操作可以重现该问题：*

1. 使用 `xxx.xxx` 方法
2. 输入 `...` 数据
3. 出现 `...` 错误
```java
public static void main(String[] args) {
List list = buildObject();
String json = JSON.toJSONString(list);
System.out.println(json);

List list2 = JSON.parseObject(json, new TypeReference>(){});
System.out.println(list2);
}

@Data
public static class RiskInfo{
private Map itemMap;
}

@Data
public static class Item {
private Long itemId;
private Map reversePriceMap;
}

@NotNull
private static List buildObject() {
RiskInfo riskInfo1 = new RiskInfo();
Item item = new Item();
item.setItemId(1L);
Map reversePriceMap = new HashMap<>();
reversePriceMap.put("1", 1L);
Map itemMap = new HashMap<>();
itemMap.put(item.getItemId(), item);
item.setReversePriceMap(reversePriceMap);
riskInfo1.setItemMap(itemMap);

RiskInfo riskInfo2 = new RiskInfo();
Item item2 = new Item();
item2.setItemId(2L);
item2.setReversePriceMap(reversePriceMap);
Map itemMap2 = new HashMap<>();
itemMap2.put(item2.getItemId(), item2);
riskInfo2.setItemMap(itemMap2);
// riskInfo2.setItemMap(itemMap);
return Lists.newArrayList(riskInfo1, riskInfo2);
}
```

### 期待的正确结果
[{"itemMap":{1:{"itemId":1,"reversePriceMap":{"1":1}}}},{"itemMap":{2:{"itemId":2,"reversePriceMap":{"$ref":"$[0].itemMap.reversePriceMap"}}}}]
[JsonRefTest2.RiskInfo(itemMap={1=JsonRefTest2.Item(itemId=1, reversePriceMap={1=1})}), JsonRefTest2.RiskInfo(itemMap={2=JsonRefTest2.Item(itemId=2, reversePriceMap={1=1})})]

### 实际输出
[{"itemMap":{1:{"itemId":1,"reversePriceMap":{"1":1}}}},{"itemMap":{2:{"itemId":2,"reversePriceMap":{"$ref":"$[0].itemMap.reversePriceMap"}}}}]
[JsonRefTest2.RiskInfo(itemMap={1=JsonRefTest2.Item(itemId=1, reversePriceMap={1=1})}), JsonRefTest2.RiskInfo(itemMap={2=JsonRefTest2.Item(itemId=2, reversePriceMap=null)})]

### 相关日志输出
暂无

#### 附加信息
*如果你还有其他需要提供的信息，可以在这里填写（可以提供截图、视频等）。*

Start with the provided Java reproducer, focusing on JSON.toJSONString and JSON.parseObject when the nested reversePriceMap instance is shared. Trace reference handling during deserialization for the emitted $ref path, then verify that both nested maps are populated instead of leaving the second one null.

Written by the indexing model from the issue text.