fix: handle created_at as string in admin users template

templates/tools/admin_users/index.html

@@ -103,7 +103,7 @@
                             {% endif %}
                         </td>
                         <td class="text-muted small">
-                            {{ user.created_at.strftime('%d/%m/%Y %H:%M') if user.created_at else 'N/A' }}
+                            {{ user.created_at[:16]|replace('T', ' ') if user.created_at else 'N/A' }}
                         </td>
                         <td>
                             <div class="table-actions">