feat: add structured economic events

world/world_view_manager.gd

@@ -33,6 +33,14 @@ func initialize_world_view() -> void:
 		simulation_manager.npc_died.connect(_on_npc_died)
 	else:
 		push_error("WorldViewManager: SimulationManager has no npc_died signal")
+	if simulation_manager.has_signal("npc_inventory_changed"):
+		simulation_manager.npc_inventory_changed.connect(
+			_on_npc_inventory_changed
+		)
+	else:
+		push_error(
+			"WorldViewManager: SimulationManager has no npc_inventory_changed signal"
+		)
 	spawn_initial_npcs()
 
 func spawn_initial_npcs() -> void:
@@ -155,3 +163,20 @@ func _on_npc_died(npc: SimNPC) -> void:
 		visual.apply_dead_visual_state()
 	else:
 		push_error("WorldViewManager: NPCVisual has no apply_dead_visual_state")
+
+func _on_npc_inventory_changed(
+	npc: SimNPC,
+	item_id: StringName,
+	amount: float
+) -> void:
+	if item_id != SimulationIds.RESOURCE_FOOD:
+		return
+	var visual = active_npc_visuals.get(npc.id)
+	if visual == null:
+		return
+	if visual.has_method("set_carried_food_visible"):
+		visual.set_carried_food_visible(amount > 0.0)
+	else:
+		push_error(
+			"WorldViewManager: NPCVisual has no set_carried_food_visible method"
+		)