[#12449] Improve validation for the Feedback Session form

[YingxuanT]

Fixes #12449

Outline of Solution

• Enhanced Field Validation: Added a validation check for the "Instructions" field in the "New Feedback Session" form. If the "Instructions" field is left empty, an error message is displayed to notify the user that the field cannot be blank.

• User Feedback: Updated the form template to display error messages below the affected fields, ensuring a clear indication of what needs to be corrected.

• Code Updates: Modified the TypeScript component to manage the validation logic, including preventing form submission when required fields are empty.

• Optional Field Addition: Added a new "Additional Information" field to provide users with an optional space for extra details.

Changes in the User Interface

• Instructions Field Validation:

If the "Instructions" field is left empty, the form displays an error message: "The Instructions field cannot be empty."

• Additional Information Field:

A new textarea labeled "Additional Information" has been added below the "Instructions" field, allowing users to provide supplementary details if needed.

Testing

• Manually tested the form to ensure that validation messages appear correctly when required fields are empty.

• Verified that the form cannot be submitted if the "Instructions" field is left blank.

[github-actions]

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