Relationship filterOptions do not updated after adding item to join field

Describe the Bug

I have a collection where you can select a default post based on the posts in a join field in that same collection.

I use the filterOption on the relationship field to only show posts that are in the join field, but this does not update when you add a new item to the join field while editing.

Because this functionality does work with a relationship field instead of a join field, I was asked (on Discord) to provide a working version with a relationship field and the broken version with the join field

• Working version with relationship field
• Broken version with join field

Link to the code that reproduces this issue

https://github.com/AaronClaes/payload-join-bug

Reproduction Steps

Step 1:

Create a join field collection without default value or posts

Step 2:

If it's created, use the "Create new Post" button from the join field and save the new post.

Step 3:

Notice how the default post select still has no possible options

Step 4:

Refresh and now the default post option is there

Remark:
You can do step 2 at any given time, it is not related to how many posts are in the join field already, step 3 will never show the newly added post

Which area(s) are affected? (Select all that apply)

area: ui

Environment Info

Binaries:
  Node: 23.5.0
  npm: 10.9.2
  Yarn: 1.22.19
  pnpm: 9.15.1
Relevant Packages:
  payload: 3.28.0
  next: 15.2.0
  @payloadcms/db-mongodb: 3.28.0
  @payloadcms/email-nodemailer: 3.28.0
  @payloadcms/graphql: 3.28.0
  @payloadcms/next/utilities: 3.28.0
  @payloadcms/payload-cloud: 3.28.0
  @payloadcms/richtext-lexical: 3.28.0
  @payloadcms/translations: 3.28.0
  @payloadcms/ui/shared: 3.28.0
  react: 19.0.0
  react-dom: 19.0.0
Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 23.6.0: Mon Jul 29 21:14:30 PDT 2024; root:xnu-10063.141.2~1/RELEASE_ARM64_T6000
  Available memory (MB): 16384
  Available CPU cores: 8

Run the linked reproduction repository first, then compare src/collections/RelationshipFieldCollection.ts with src/collections/JoinFieldCollection.ts. Reproduce adding a post through the join field and observe the default post filter before and after a refresh. Done means the newly added post appears as an option without refreshing the page, while the existing relationship-field behavior remains intact.