Always field ServerClientIdConfirms by responding with a ClientDeviceListAnnounceRequest (#18365)
Always field ServerClientIdConfirms by responding with a ClientDeviceListAnnounceRequest (#18365)

that contains smartcard info, rather than previous behavior of only doing
so once and then just returning an empty ClientDeviceListAnnounceRequest.

This allows us to run commands like `certutil -scinfo` and receive data
back about Teleport's virtual smartcard.
gravitational/teleport,gravitational/teleport,gravitational/teleport,gravitational/teleport,gravitational/teleport,gravitational/teleport