Typescript: get type of first property of type

I get a nested object as result of a GraphQL query with the query name as first-level key and the actual data on the second level:

{
    getProduct: {
        id: "1",
        name: "test",
    }
}

In my query function I automatically extract the first key of the object and return the value of getProduct. However, I would like to infer the type of the first key as the return value of the query function.

type QueryReturn = FirstElement<GetProductQuery>; // should be { id: string; name: string }

All solutions I've found on the Internet infer the Head or Tail of an Array or Function.

I'm a bit late to the party but I saw that you were using graphql-codegen. I had a similar problem which I solved with:

type DataType = {
  __typename?: string;
};

type FilteredQuery<T> = {
  [P in keyof T as T[P] extends DataType ? P : never]: T[P];
};

type QueryData<T> = FilteredQuery<T>[keyof FilteredQuery<T>];

TypeScript playground example.