[FEATURE] Allow passing related objects as id for creating objects

[bmikaili]

Currently, json has to be written like this to create objects:

{
  "name": "Account",
  "user": {
    "id": "26132E11-6D13-4983-9FAE-71B705439BD8"
  }
}

It would be nice to only have to do this:

{
  "name": "Account",
  "user": "26132E11-6D13-4983-9FAE-71B705439BD8"
}

This should be possible with DTOs.

[bmikaili]

@PSchmiedmayer is the use case for this only when doing manual JSON requests? As far as I know, when sending requests through a client, everything goes through Codable, so the user is not really exposed to this syntax.

[bmikaili]

This is currently a limitation of Fluent, because it expects an actual object as part of a Model, not just an id reference.