For HBI it is theoretically possible that they could send us a completely empty reporter representation as none of their reporter information is required - https://github.com/project-kessel/inventory-api/blob/main/data/schema/resources/host/reporters/hbi/host.json

However, when reporting a resource with an empty reporter object or all null fields, we produce a 500 error.

{
    "code": 500,
    "reason": "",
    "message": "transaction failed: invalid reporter representation: representation data cannot be empty",
    "metadata": {}
}

We need to allow reporter to be empty and return a 200 if there are no other validation errrors

Slack context: https://redhat-internal.slack.com/archives/C059NUD49PD/p1757432714188059