Validation does not work fine for a form field without an associated component

[Jaime02]

Describe the bug

Hello, I am using a form with a field which is not associated to a <form.AppField> component.

OLD BEHAVIOUR tanstack-form version 1.23.8:
Initially, I am getting a validation error, which is correct. Then I change the field value using form.setFieldValue to a valid value, but the form validation error is still there.

NEW BEHAVIOUR tanstack-form version 1.27.5:
The validation errors are not shown at all ☹️

Your minimal, reproducible example

OLD EXAMPLE tanstack-form version 1.23.8:
https://stackblitz.com/edit/tanstack-form-kurxzdck?file=src%2Findex.tsx

NEW EXAMPLE tanstack-form version 1.27.5:
https://stackblitz.com/edit/tanstack-form-bgycyyay

Steps to reproduce

1. Create a form. Define a field without an associated HTML component.
2. The form validation will not work fine, changing the field value using form.setFieldValue will not update the form validation state properly

Expected behavior

A form field should not require an associated component for the validation to work properly

How often does this bug happen?

Every time

Platform

Windows
Chrome
@tanstack/react-form@1.23.8, @tanstack/react-form@1.27.5

TanStack Form version

1.23.8, 1.27.5

(Updated 21/12/25 because the behaviour of the bug has changed in the latests tanstack/react-form updates)