feat: relationship sortOptions property (#4301)

* feat: adds sortOptions property to relationship field

* chore: fix lexical int tests

* feat: simplifies logic & updates joi schema definition

* feat: revert to default when searching in relationship select

* fix types and joi schema

* type adjustments

---------

Co-authored-by: Alessio Gravili <alessio@bonfireleads.com>
Co-authored-by: Jarrod Flesch <jarrodmflesch@gmail.com>

packages/plugin-nested-docs/src/fields/parent.ts

@@ -1,13 +1,13 @@
-import type { RelationshipField } from 'payload/types'
+import type { SingleRelationshipField } from 'payload/types'
 
 const createParentField = (
   relationTo: string,
   overrides?: Partial<
-    RelationshipField & {
+    SingleRelationshipField & {
       hasMany: false
     }
   >,
-): RelationshipField => ({
+): SingleRelationshipField => ({
   name: 'parent',
   relationTo,
   type: 'relationship',