Module registry 

ComponentRegistry: ordered, dependency-aware, type-erased registry for every Component in the runtime.

Responsibilities

• Registration: ComponentRegistry::register_factory queues a component kind for initialization.
• Dependency resolution: factory metadata lists depends_on names; the registry topologically sorts the graph and refuses to proceed if a cycle is present.
• Type erasure: components are stored as Arc<dyn AnyComponent> so the registry can hold heterogeneous instances. Typed access uses ComponentRegistry::get to downcast back to a concrete Arc<C>.
• Lifecycle orchestration: ComponentRegistry::init_all, ComponentRegistry::start_all, ComponentRegistry::stop_all drive the four-phase component lifecycle in dependency order.
• Health aggregation: ComponentRegistry::health fans out AnyComponent::health calls concurrently and collects the results into a single map for /healthz responses.

Lifecycle ordering

  register(...)        # queues factory
      ↓
  init_all()           # topo order, dep-first
      ↓
  start_all()          # topo order
  ... serve ...
      ↓
  stop_all()           # reverse topo order

On init error, the registry leaves the offending component in a ComponentState::Failed state and continues to attempt initialization of any components that do not depend on it. This maximizes operator visibility: a single broken optional backend should not prevent the rest of the system from coming up.

Structs

ComponentDescriptor

Static descriptor of a component kind, used by the registry to plan initialization order without holding the actual factory.

ComponentRegistry

The central component registry.

TypedAnyComponent

Adapter from a typed Component to the type-erased AnyComponent trait. Created by TypedFactory::build.

TypedFactory

Convenience wrapper that adapts a concrete Component into a ComponentFactory.

Enums

ComponentState

Initialization state of a registered component.

RegistryError

Errors raised by ComponentRegistry operations.

Traits

ComponentFactory

Type-erased factory for a concrete Component type. The registry holds factories as Box<dyn ComponentFactory> so it can drive heterogeneous types uniformly.