This will be needed to support preauth-keys with network lock in the future,
so getting the core mechanics out of the way now.
Signed-off-by: Tom DNetto <tom@tailscale.com>
Following the pattern elsewhere, we create a new tka-specific types package for the types
that need to couple between the serialized structure types, and tka.
Signed-off-by: Tom DNetto <tom@tailscale.com>