artifact: infrastructure/src/main/kotlin/com/correx/infrastructure/InfrastructureModule.kt
purpose: Add createRouterFacade() factory that assembles RouterFacade from RouterRepository, RouterContextBuilder, InferenceRouter, EventStore, and RouterConfig.
depends_on: task-013, task-002
non_goals: Creating router types (all done in earlier tasks), modifying ServerModule
done_when: createRouterFacade() returns a fully wired RouterFacade and ./gradlew check passes
