Fetch field value passed as query parameter from URL and set the value on the field

[Soumyadeep10]

PR Description:

This piece of code is designed for an usecase where you might want to populate a field value that you're passing as a query in the URL which redirects to a catalog item.
In this case, a custom field 'u_date' is chosen as an example to be shown:

1. You open a catalog item record via a URL that carries a date in the query string.
   Example:
   https://your-instance.service-now.com/your_form.do?sysparm_u_date=2025-10-31
   -(This URL includes a parameter named sysparm_u_date with the value 2025-10-31.)

2. The catalog client script reads the page URL and extracts that specific parameter which returns the value "2025-10-31".

3. If the parameter is present, the script populates the form field.
   Calling g_form.setValue('u_date', '2025-10-31') sets the date field on the form to 31 October 2025.

Result:
The date field in the form is prefilled from the URL

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[ravichandra1998g]

• Thank you for submitting, looks good!

[Soumyadeep10]

Thank you @ravichandra1998g !!