AgentSpaces in Groovy's idiom: extension methods on the Space API and the capability clients, coercions, the fleet and agent DSLs, the FleetScript base class, the async twins, the FleetChecker type-checking extension, and the FleetShell. Depends only on stable Groovy 6 features.

Channels over space subscriptions, broadcast, select, and dataflow twins over Groovy 6's groovy.concurrent toolkit, which Groovy marks incubating. Every use of that package lives here and nowhere else in the project.