Split the action "Suitcase Nuke"
Stop relying on the Spy unit type flag to decide if the "Suitcase Nuke" action consumes the actor unit. Split the new action "Suitcase Nuke Escape" from "Suitcase Nuke". The former will have its actor try to escape. The latter will always consume the actor unit.
This makes it possible to create a ruleset where all actor units, including those with the Spy utype flag, are consumed when suitcase nuking a city. It makes the opposite (everyone, including non Spy units, escapes) possible too. It also makes more complex rules, like "only veterans has a chance of escaping after placing the suitcase", possible.