Dedicated Dishwasher Role, Real Kitchen Door

Added a real walkable kitchen door (with actual swinging-door art, distinct from the food-handoff pass tile) after discovering busboys assigned to wash dishes had no physical path into the kitchen at all — the counter wall separating kitchen from dining had exactly one gap (the pass), which is an interaction point, not a walkable passage. Added a dedicated dishwasher role (hireable, spawns at the sink) to own washing and resetting dishes end to end; busboy and cook no longer touch that job, keeping busboy purely front-of-house.