feat(useForm): improve type parameter specification to useForm

[OmkarBansod02]

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What is the current behavior?

The useForm hook uses a single type parameter for both the form structure and the data submitted to the API. This causes type conflicts when trying to map form data into the structure needed for the API . As a result, developers encounter type errors when attempting to submit transformed data.

What is the new behavior?

After the changes, the useForm hook introduces an additional type parameter for submission data . This separates the form structure type from the submission type . onFinish function correctly expects the SubmissionData type instead of the form structure type. allowing developers to easily map and submit the data without running into type issues.

fixes #6137

Notes for reviewers

The onValid function is wrapped in onValidWrapper to address a TypeScript error where the form data (TVariables) does not match the expected structure for onValid. This results in a type conflict, so use type casting (variables as unknown as ExtractFormVariables<TVariables>) to ensure the correct form data type is passed to onValid. This resolves the error and ensures type safety during form submission.

[changeset-bot]

🦋 Changeset detected

Latest commit: d0ce6ee

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@refinedev/react-hook-form	Minor
@refinedev/core	Minor

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[BatuhanW]

Why do we need these?

[OmkarBansod02]

here we use Symbol for FormVariables and SubmissionVariables to ensure uniqueness and avoid conflicting with the basic TVariables shape. as Ali mentioned here .

[aliemir]

Thank you for the PR @OmkarBansod02

I've reviewed your changes. These looks aligned with my initial comment to the issue but missing the implementation in @refinedev/antd, @refinedev/mantine and @refinedev/react-hook-form. There are changes in @refinedev/react-hook-form but I'm not sure if the exported methods and props reflects those changes properly.