Url creation for the search form should use Drupal functions

Problem/Motivation

When using multisites this module doesn't work.
Code should use Drupal functions whereever possible so Url generation works flawlessly.

Steps to reproduce

Have a multisite and use the search form (On a configured content type you should clikc "ChatGPT Content Generator") You wil be redirect to another site.

Proposed resolution

Use Drupal functions where possible, in this case "Url::fromUserInput()"

Remaining tasks

Review