[vsphere]: syslog grok patterns do not support formats with structured data

### Integration Name

VMware vSphere [vsphere]

### Dataset Name

log

### Integration Version

1.22.0

### Agent Version

n/a

### Agent Output Type

elasticsearch

### Elasticsearch Version

n/a

### OS Version and Architecture

n/a

### Software/API Version

_No response_

### Error Message

_No response_

### Event Original

_No response_

### What did you do?

ingested a syslog RFC5424-style message with structured data. the specific example is:

```
<14>1 2025-10-03T17:13:06.747Z some.host.name.com localcli 28451738 - [Originator@6876 priority="info" facility="user"] 28451738:VVOLLIB : VVolLib_SetLogLevel:1351: Log level for vvolLib set to 10
```

### What did you see?

the first syslog grok pattern[1], which targets RFC5424-style messages, does not match due to the structured data in the messsage. the second syslog grok pattern[2] matches instead, but since it's designed for RFC3164-style messages, causes the extracted fields to be incorrect.

in particular, we see the following result from the grok processor:

```
{
"process": {
"name": "localcli 28451738 - [Originator@6876 priority=\"info\" facility=\"user\"] 28451738:VVOLLIB "
},
"_tmp": {
"timestamp": "2025-10-03T17:13:06.747Z"
},
"log": {
"syslog": {
"priority": 14
}
},
"host": {
"name": "some.host.name.com"
},
"message": "VVolLib_SetLogLevel:1351: Log level for vvolLib set to 10",
...
}
```

[1] `^(%{ECS_SYSLOG_PRIORITY})?%{TIMESTAMP_ISO8601:_tmp.timestamp}%{SPACE}%{HOST}%{SPACE}%{NOTSPACE:process.name} (%{POSINT:process.pid:long}|-) - -%{SPACE}%{GREEDYDATA:message}`
[2] `^(%{ECS_SYSLOG_PRIORITY})?%{TIMESTAMP_ISO8601:_tmp.timestamp}%{SPACE}%{HOST}%{SPACE}%{DATA:process.name}(?:\[%{POSINT:process.pid:long}\])?\: %{GREEDYDATA:message}`

### What did you expect to see?

we expect to see `"process.name": "localcli"`, `"process.pid": 28451738`, `"message": "28451738:VVOLLIB : VVolLib_SetLogLevel:1351: Log level for vvolLib set to 10"`

### Anything else?

we should add support for structured data to the syslog grok patterns.