Need Ceph NVMeMon map response to be Json compatible

Need JSON reponse for the NVMeMON map command response, it might help us in easy way of parsing data.

```$ ceph nvme-gw show rbd ''
{
"pool": "rbd",
"group": "",
"num gws": 2,
"Anagrp list": "[ 2 1 ]"
}
{
"gw-id": "client.nvmeof.rbd.ceph-sunilkumar-00-7v6gmf-node6.ltohgy",
"anagrp-id": 2,
"last-gw_map-epoch-valid": 1,
"Availability": "AVAILABLE",
"ana states": " 2: OWNER_FAILBACK_PREPARED , 1: STANDBY ,"
}
{
"gw-id": "client.nvmeof.rbd.ceph-sunilkumar-00-7v6gmf-node7.qraoia",
"anagrp-id": 1,
"last-gw_map-epoch-valid": 1,
"Availability": "AVAILABLE",
"ana states": " 2: WAIT_FAILBACK_PREPARED , 1: ACTIVE ,"
}
```

**Validate Json fails**
```
>>> import json
>>> data = """{
... "pool": "rbd",
... "group": "",
... "num gws": 2,
... "Anagrp list": "[ 2 1 ]"
... }
... {
... "gw-id": "client.nvmeof.rbd.ceph-sunilkumar-00-7v6gmf-node6.ltohgy",
... "anagrp-id": 2,
... "last-gw_map-epoch-valid": 1,
... "Availability": "AVAILABLE",
... "ana states": " 2: OWNER_FAILBACK_PREPARED , 1: STANDBY ,"
... }
... {
... "gw-id": "client.nvmeof.rbd.ceph-sunilkumar-00-7v6gmf-node7.qraoia",
... "anagrp-id": 1,
... "last-gw_map-epoch-valid": 1,
... "Availability": "AVAILABLE",
... "ana states": " 2: WAIT_FAILBACK_PREPARED , 1: ACTIVE ,"
... }"""
>>>
>>> json.loads(data)
Traceback (most recent call last):
File "", line 1, in
File "/usr/lib64/python3.9/json/__init__.py", line 346, in loads
return _default_decoder.decode(s)
File "/usr/lib64/python3.9/json/decoder.py", line 340, in decode
raise JSONDecodeError("Extra data", s, end)
json.decoder.JSONDecodeError: Extra data: line 7 column 1 (char 87)
```

Start with the implementation of the `ceph nvme-gw show` NVMeMON map command and trace how its response is formatted. Make the complete output valid JSON while preserving the pool, gateway, and ANA state data shown in the issue. Validate the result with Python's `json.loads` using the reproduced response.

Written by the indexing model from the issue text.