[app-server & core] introduce new codex error code and v2 app-server error events (#6938)
This PR does two things:
1. populate a new `codex_error_code` protocol in error events sent from
core to client;
2. old v1 core events `codex/event/stream_error` and `codex/event/error`
will now both become `error`. We also show codex error code for
turncompleted -> error status.
new events in app server test:
```
< {
< "method": "codex/event/stream_error",
< "params": {
< "conversationId": "019aa34c-0c14-70e0-9706-98520a760d67",
< "id": "0",
< "msg": {
< "codex_error_code": {
< "response_stream_disconnected": {
< "http_status_code": 401
< }
< },
< "message": "Reconnecting... 2/5",
< "type": "stream_error"
< }
< }
< }
{
< "method": "error",
< "params": {
< "error": {
< "codexErrorCode": {
< "responseStreamDisconnected": {
< "httpStatusCode": 401
< }
< },
< "message": "Reconnecting... 2/5"
< }
< }
< }
< {
< "method": "turn/completed",
< "params": {
< "turn": {
< "error": {
< "codexErrorCode": {
< "responseTooManyFailedAttempts": {
< "httpStatusCode": 401
< }
< },
< "message": "exceeded retry limit, last status: 401 Unauthorized, request id: 9a1b495a1a97ed3e-SJC"
< },
< "id": "0",
< "items": [],
< "status": "failed"
< }
< }
< }
```
9bce050385