The Applications page had no delete control even though the endpoint and
the API client both already existed, so the gap was UI-only.
The button is gated on applications.delete via hasPermission rather than
on the admin role, mirroring the backend guard: admins bypass it anyway,
and a non-admin role granted the permission should get the button instead
of a control that would only 403.
Deleting also withdraws the generated install policy. Delete here is a
soft delete, and the policy is a separate row that did not follow, so a
deactivated application kept installing itself across the fleet with
nothing on screen to explain why. A customised policy is still left
alone, on the same ownership terms as unticking the box.