Error with Data size larger than 1M, will not write to zk. Data (first 1k)

This is not critical but shows some problems worth investigating.

Our QA cluster is having trouble with some accumulated data. It has 10k+ real time segments in place, data are not too much.

In logs we see something like below:
```
2021/11/04 20:31:34.166 ERROR [ZkClient] [HelixTaskExecutor-message_handle_thread] Data size larger than 1M, will not write to zk. Data (first 1k): {
"id" : "point_entry_REALTIME",
"simpleFields" : {
"BATCH_MESSAGE_MODE" : "false",
"BUCKET_SIZE" : "0",
"SESSION_ID" : "30069443a0581e1",
"STATE_MODEL_DEF" : "SegmentOnlineOfflineStateModel",
"STATE_MODEL_FACTORY_NAME" : "DEFAULT"
},
"mapFields" : {
"point_entry__0__0__20211030T0056Z" : {
"CURRENT_STATE" : "OFFLINE"
},
"point_entry__0__100__20211102T0746Z" : {
"CURRENT_STATE" : "OFFLINE"
},
"point_entry__0__101__20211102T0817Z" : {
"CURRENT_STATE" : "OFFLINE"
},
"point_entry__0__102__20211102T0909Z" : {
"CURRENT_STATE" : "OFFLINE"
},
"point_entry__0__103__20211102T0946Z" : {
"CURRENT_STATE" : "ONLINE",
"END_TIME" : "1636056441791",
"INFO
```

Start by tracing the ZkClient write path associated with the logged size-limit error and examine how the accumulated real-time segment data reaches it. Reproduce the issue with data larger than 1M and document a verified outcome for handling or reporting that condition.

Written by the indexing model from the issue text.