Simulation — triggered & replacement effects

These scenarios run through the procedural machine (in @acme/game-logic/sim): abilities subscribe to events (triggered abilities) and deaths are threaded through replacement effects before they resolve — the same two MtG subsystems by name. The layer-system fold still handles continuous statuses (poison, protection) underneath. Several of these outcomes — Mayor bounce, Ravenkeeper, Scarlet Woman, star-pass — cannot be expressed by the layer system alone.