I am developing a helpdesk ticketing system for my main website, and I'm looking for best practices to integrate the userbase. the ticketing system should work as an external system and in the future, I'm looking forward to developing and adding more external systems to the main website such as CRM, etc. and Also I want to use the ticketing system for other projects as well.
both the ticketing system and main website are based on the laravel framework and my main website has existing users. I want these two platforms to work as one, simultaneously but in a way that users don't have to log in twice or be bothered by the separation in the back. currently, all the signed-up users are stored on the main website DB.
for authentication purposes, I guess I need to use JWT. but what are the best ways and designs to integrate userbase and user events like sign up, etc? note that the users in each system might have extra attributes and details as well as some shared attributes.