Create admin dashboard page for users management

[GabrielMajeri]

We should create a page in the admin interface (for example, at the /admin/users path) to allow for the viewing, creation, editing and removal of users (with roles).

This page will only list the users which have an administrative role assigned to them (i.e. we will not store or display the anonymous users who use the app without logging in). Therefore, we can expect this page to only have a handful of users. That being said, it's still a good idea to use TanStack Query to load and cache them (it also has support for server-side rendering).

The page will consist of a list/table showing all of the users (possibly implemented using TanStack Table), with the following columns:

• ID
• Name
• E-mail
• Role
• Actions (edit/delete)

Since we do not store the user's name or e-mail in the database, we can retrieve them dynamically by using a batch request to the Microsoft Graph API. Check out this tutorial on how to use the Microsoft Graph SDK to fetch data in React.

We should also have an "add user" button which will allow us to allocate roles to new users. This could be a separate page (for example, /admin/users/new) on which you can search for an user in the Microsoft 365 tenant by their name/e-mail, select them and give them a role.