Build a data table in React that displays a list of users and allows sorting by columns.

Requirements:

1. Display user data in a table with columns: Name, Age, and Email.
2. Add sorting functionality:
   • Clicking on a column header sorts the table by that column.
   • Clicking again toggles ascending/descending order.
3. Indicate which column is currently sorted.
4. Sorting should work for both text and numbers.
5. Focus on functionality over styling.