STDOUT producing malform JSON

### Report

Report
Following issues:

HTTP error value incorrectly set
```
{"level":"Verbose","timestamp":"2026-03-02T21:01:19.4676972Z","eventType":"ResponseReceivedInFull","apiId":"open-wilcosandbox2-api-api","operationId":"open-wilcosandbox2-api-operation-420","tags":0,"httpMethod":"POST","source":"Http1UpstreamResponseHandler","serviceName":"apim-gateway","transportError":0,"httpError":0,"payloadBuffered":0}{
azure-apim-gateway-azure-api-management-gateway-db97fb964-pbjdv "isRequestSuccess":true{"level":"Verbose","timestamp":",2026-03-02T21:01:19.4677028Z","eventType":"ChannelLeaseReturned","apiId":"open-wilcosandbox2-api-api","operationId":"totalTime":"open-wilcosandbox2-api-operation-420","tags":0,"267httpMethod":,"category""POST","source"::"Http1Connections-ChannelPool#9#100.64.28.241:443#tls=weil-sand.opensandbox2.company.com:Tls12:False:False:-464039545;proxy=;port=443","serviceName":""apim-gateway"GatewayLogs","message":,"callerIpAddress":""channel=[id: 0x5691b4a0, L:100.112.7.140:57728 - R:100.64.28.241:443]","transportError":0,"httpError":100.112.16.138","timeGenerated":"2026-03-02T21:01:19.2003054Z"0,"payloadBuffered":,"region":"eastus"0}
```
Another issue,
```
{"level":"Verbose","timestamp":"2026-03-02T21:29:57.2022958Z","eventType":"ResourceCountChanged","message":{"2 -> 3","source":"isRequestSuccess":true,"totalTime":141,"category":"GatewayLogs","callerIpAddress":"100.112.16.138""Http1Connections-ChannelPool#1#100.64.28.241:443#tls=cohenseglias-sand.opensandbox2.company.com:Tls12:False:False:-810888139;proxy=;port=443"}
,"timeGenerated":"2026-03-02T21:29:57.0607332Z","region":"eastus","correlationId":"2e573d72-d273-47e1-8c58-ac37b1b3c4d6","method":"PATCH","url":"https://cohenseglias-sand.opensandbox2.company.com/open/wilcosandbox2/api/api/api/common/v1/clients/57550","backendResponseCode":200,"responseCode":200,"responseSize":2991,"cache":"none","backendTime":140,"requestSize":1625,"apiId":"open-wilcosandbox2-api-api","operationId":"open-wilcosandbox2-api-operation-63","clientProtocol":"HTTP/1.1","backendProtocol":"HTTP/1.1","backendId":"open-wilcosandbox2-api-backend","apiRevision":"1","clientTlsVersion":"1.3","backendMethod":"PATCH","backendUrl":"https://wilcosandbox2-api.open.svc.cluster.local/api/api/common/v1/clients/57550"}

```

### Expected Behavior

Shall not produce error

### Actual Behavior

```
{"level":"Verbose","timestamp":"2026-03-02T21:01:19.4676972Z","eventType":"ResponseReceivedInFull","apiId":"open-wilcosandbox2-api-api","operationId":"open-wilcosandbox2-api-operation-420","tags":0,"httpMethod":"POST","source":"Http1UpstreamResponseHandler","serviceName":"apim-gateway","transportError":0,"httpError":0,"payloadBuffered":0}{
azure-apim-gateway-azure-api-management-gateway-db97fb964-pbjdv "isRequestSuccess":true{"level":"Verbose","timestamp":",2026-03-02T21:01:19.4677028Z","eventType":"ChannelLeaseReturned","apiId":"open-wilcosandbox2-api-api","operationId":"totalTime":"open-wilcosandbox2-api-operation-420","tags":0,"267httpMethod":,"category""POST","source"::"Http1Connections-ChannelPool#9#100.64.28.241:443#tls=weil-sand.opensandbox2.company.com:Tls12:False:False:-464039545;proxy=;port=443","serviceName":""apim-gateway"GatewayLogs","message":,"callerIpAddress":""channel=[id: 0x5691b4a0, L:100.112.7.140:57728 - R:100.64.28.241:443]","transportError":0,"httpError":100.112.16.138","timeGenerated":"2026-03-02T21:01:19.2003054Z"0,"payloadBuffered":,"region":"eastus"0}
```

### Steps to Reproduce the Problem

1.
2.
3.

### Logs from self-hosted gateway

```
{"level":"Verbose","timestamp":"2026-03-02T21:01:19.4676972Z","eventType":"ResponseReceivedInFull","apiId":"open-wilcosandbox2-api-api","operationId":"open-wilcosandbox2-api-operation-420","tags":0,"httpMethod":"POST","source":"Http1UpstreamResponseHandler","serviceName":"apim-gateway","transportError":0,"httpError":0,"payloadBuffered":0}{
azure-apim-gateway-azure-api-management-gateway-db97fb964-pbjdv "isRequestSuccess":true{"level":"Verbose","timestamp":",2026-03-02T21:01:19.4677028Z","eventType":"ChannelLeaseReturned","apiId":"open-wilcosandbox2-api-api","operationId":"totalTime":"open-wilcosandbox2-api-operation-420","tags":0,"267httpMethod":,"category""POST","source"::"Http1Connections-ChannelPool#9#100.64.28.241:443#tls=weil-sand.opensandbox2.company.com:Tls12:False:False:-464039545;proxy=;port=443","serviceName":""apim-gateway"GatewayLogs","message":,"callerIpAddress":""channel=[id: 0x5691b4a0, L:100.112.7.140:57728 - R:100.64.28.241:443]","transportError":0,"httpError":100.112.16.138","timeGenerated":"2026-03-02T21:01:19.2003054Z"0,"payloadBuffered":,"region":"eastus"0}
```

### Self-hosted Gateway Version

2.11.0

### Deployment

Self-Managed (YAML/Helm)

### Platform

Microsoft Azure

### Kubernetes Version

1.26

### Anything else?

_No response_

Start by reproducing the malformed stdout logs with self-hosted gateway version 2.11.0 deployed through YAML/Helm on Kubernetes 1.26 in Azure. Compare the reported ResponseReceivedInFull and ChannelLeaseReturned records with the expected JSON structure; done means each emitted log record is valid JSON without interleaved or corrupted fields.

Written by the indexing model from the issue text.