[Feature Request] - add "metadata" key=value pairs when creating session

[devlikepro]

For integration purpose with application it can be useful to give a way to add additional "application related" data in session. After that, we'll send

1. metadata back to the system in webhook event, so the app can easily match records in their database
2. Show it on Dashboard so you can quickly search the desired session by using application and user data

For instance

{
  "name": "default",
  "metadata": {
    "user.id": 123,
    "user.email": "[email protected]"
  }
}

would give session.status event

{
    "event": "session.status",
    "session": "default",
    "me": {
        "id": "[email protected]",
        "pushName": "~"
    },
     "metadata": {
      "user.id": 123,
      "user.email": "[email protected]"
    }
    "payload": {
        "status": "WORKING"
    },
    "engine": "WEBJS",
    "environment": {
        "version": "2023.10.12",
        "engine": "WEBJS",
        "tier": "PLUS"
    }
}