type-graphql hack/scalar for Nested field validation - take inspiration from this (and even just see if it works!)

Nested.ts

import { Field } from 'type-graphql';
import { ValidateNested } from 'class-validator';
import { plainToClass } from 'class-transformer';

export function Nested(options?: { each?: boolean; nullable?: boolean }) {
  return (target: any, propertyName: string) => {
    const Ctx = Reflect.getMetadata(
      'design:type',
      target.constructor.prototype,
      propertyName
    );

    if (options && options.each) {
      Field(() => [Ctx], { nullable: options.nullable })(target, propertyName);
    } else {
      Field(() => Ctx, { nullable: options ? options.nullable : false })(
        target,
        propertyName
      );
    }
    ValidateNested()(target, propertyName);

    Object.defineProperty(target.constructor.prototype, propertyName, {
      get() {
        return this[`__${propertyName}`];
      },
      set(value: any) {
        this[`__${propertyName}`] = plainToClass(Ctx, value);
      },
    });
  };
}