Reference field options must be nested under the options key

Reference field options such as `filter` must be nested under the `options` key, not placed on the root of the reference type.

The reference field lets you define options for the input component. Define these options under the options key.

Sanity Studio reports `filter` is not allowed on a reference type definition - did you mean `options.filter`? when you place reference options on the root of the type instead of inside options. The same message is emitted for filterParams.

import {defineField, defineType} from 'sanity'

export default defineType({
  name: 'blogPost',
  type: 'document',
  fields: [
    defineField({
      name: 'author',
      type: 'reference',
      to: [{type: 'person'}],
      options: {
        filter: 'age > 30',
      },
    }),
  ],
})