title: NestJS - How to create nested schema with decorators
body: <p>Let's say I want to build the below schema with mongoose:</p>
  <pre class="lang-js prettyprint-override"><code>const userSchema = new Schema({
    name: {
      firstName: String,
      lastName: String
    }
  })
  </code></pre>
  <p>How can I do it with NestJS decorators (<code>@Schema()</code> &amp; <code>@Prop()</code>)?</p>
  <p>I try this method, but no luck:</p>
  <pre class="lang-js prettyprint-override"><code>@Schema()
  class Name {
    @Prop()
    firstName: string;
  
    @Prop()
    lastName: string;
  }
  
  @Schema()
  class User extends Document {
    @Prop({ type: Name })
    name: Name;
  }
  </code></pre>
  <p>I also don't want to use the <code>raw()</code> method.</p>