Add top level log attributes

[JeloneKK]

For example, if the log configuration is json, it produces an output like this
{
"timestamp": "2023-10-30T14:09:34.771388Z",
"level": "INFO",
"message": "My custom message"
}

what I need is to be able to add top level log attribute, e.g.
{
"timestamp": "2023-10-30T14:09:34.771388Z",
"level": "INFO",
"message": "My custom message",
"_aws": {
"CloudWatchMetrics": [ ... ]
}
}

And it looks like this is not possible right now.

[BrynCooke]

We're looking to implement something to allow this soon.