Type parameter hints

[evestera]

E.g.

{
  "/hits/hits/-/_source": {
    "type_parameter": "T"
  }
}

or

{
  "/hits/hits/-/_source": {
    "use_type": "type_parameter"
  }
}

For typescript/typealias this is already possible with just adding <T> to the type name and using

{
  "/hits/hits/-/_source": {
    "use_type": "T"
  }
}