lifecycle/
├── types.ts              # Phase, LifecycleState, ServiceMetadata, Pausable, errors
├── decorators.ts         # @Injectable, @ServicePhase, @DependsOn, @Priority, etc.
├── BaseService.ts        # Abstract base class with lifecycle hooks
├── event.ts              # Emitter<T>, Event<T>, Disposable — typed inter-service events
├── signal.ts             # Signal<T> — one-shot deferred value (PromiseLike)
├── ServiceContainer.ts   # IoC container with DI and conditional activation
├── DependencyResolver.ts # Topological sort, layered parallel resolution
├── LifecycleManager.ts   # Phased bootstrap, shutdown, pause/resume/stop/start
├── index.ts              # Barrel export
└── __tests__/            # Unit tests for all components