SimpleDesign back to skeleton LoadedComponents that the existing simulation creation accepts - the bridge that lets the dotnet sidecar run today's simulator on a design that arrived over the wire, as a BASELINE against which rewrites (and the Electron simulator itself) can be checked. Deliberately not part of the wire contract: the Simple types stay minimal, and a future .NET simulator consumes them directly with its own structures. This shim reconstructs only what the current pipeline demands - components with port lists (ports synthesized from the component type's arity; port ids never crossed the wire), connections resolved back from (component, port number) endpoints, and sheet IO signatures recomputed by the same function the loader uses. Geometry stays zeroed: the simulator never reads it.