Added a few more tests

[snipe]

This PR reshuffles a few of the tests on users, adds a few more, and adds some translation strings. I also discovered a few missing checks (in the process of writing those tests) that I realized we weren't doing, which could potentially allow someone to delete a user that still managed other users, locations, etc. We prevent this on the front-end of course, but we weren't enforcing it on the back end.

[what-the-diff]

PR Summary

• Enhanced User Searching and Filtering
  Changes were made in the UsersController.php file to improve user search functionality in our API. Users can now be searched and filtered based on their activation status and location. Also, there is an option to include deleted users within the search results if needed.

• Restrictions on User Deletion
  We've made our system smarter by adding checks to prevent the deletion of a user under certain conditions. These conditions include if a user is trying to delete themselves, or if the target user is tied to assets, licenses, accessories, managed locations, or manages other users.

• Improved Deletion Prompts
  Upgrades to the system now notify users about the reasons why a certain user cannot be deleted. These could be due to user being linked to assets, licenses, accessories, locations they manage or users under their control. Appropriate error messages have been framed and added to support this feature.

• Enhanced Test Coverage for Deleting Users
  We’ve introduced two new test suites in both the API and web interfaces to validate our new restrictions on user deletion. These tests ensure that our system is working as expected in different user deletion scenarios.