## Description
<ins>Problem</ins>
When deleting all fields of array item, submit became disabled.
<ins>Root cause</ins>
The JSON form widget did not properly handle field validation during
unmounting of array items, leading to inconsistencies in the form's
error state.
<ins>Solution</ins>
This PR implements `useUnmountFieldValidation` to `FieldRenderer.tsx`,
enhancing field validation for array items in the JSON form widget. This
PR handles...
- Ensuring proper cleanup of field validation when an array field is
removed from the form, resolving visibility issues in list view mode.
- Maintaining a consistent and accurate form state even after field
removal.
Fixes#18752
_or_
Fixes `Issue URL`
> [!WARNING]
> _If no issue exists, please create an issue first, and check with the
maintainers if the issue is valid._
## Automation
/ok-to-test tags="@tag.JSONForm"
### 🔍 Cypress test results
<!-- This is an auto-generated comment: Cypress test results -->
> [!TIP]
> 🟢🟢🟢 All cypress tests have passed! 🎉🎉🎉
> Workflow run:
<https://github.com/appsmithorg/appsmith/actions/runs/11703351095>
> Commit: 521fd25a83c099ddcc0273cf11b4cca80074c7a5
> <a
href="https://internal.appsmith.com/app/cypress-dashboard/rundetails-65890b3c81d7400d08fa9ee5?branch=master&workflowId=11703351095&attempt=1"
target="_blank">Cypress dashboard</a>.
> Tags: `@tag.JSONForm`
> Spec:
> <hr>Wed, 06 Nov 2024 12:45:42 UTC
<!-- end of auto-generated comment: Cypress test results -->
## Communication
Should the DevRel and Marketing teams inform users about this change?
- [ ] Yes
- [ ] No
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
- **New Features**
- Introduced a new mechanism for handling field validation upon
unmounting in the form widget.
- **Bug Fixes**
- Improved field validation logic to enhance form data management during
component unmounting.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->