Fix file request dialog keeps asking for upload destination if ignored for the first time

[falghamdi125]

Hello everyone,

• Resolves: [Bug]: File request dialog keeps asking for upload destination if ignored the first time... even after going back to select a destination #48118

Summary

This PR fixes the issue in the validation process of the file request dialog. If you did not enter a destination folder and click next, the dialog fails to clear the first reported validity status.

This PR resolves an issue in the validation process of the file request dialog. Previously, if no destination folder was entered and the 'Next' button was clicked, the dialog failed to reset the initial validity status, leading to incorrect validation feedback.

What I did was:

• Prevented going to the next step if the destination folder is invalid.
• Added helper text to inform users that selecting the root folder is not allowed.
• Cleared the error message and helper text once a valid path is selected.

@skjnldsv

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)

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[skjnldsv]

Hey, thanks for the PR!
Unfortunately your approach isn't really fixing the real issue, which is that the custom validty needs to be reset.

Fix in #50524