Give a healing potion too for testing.

worldbuilder.cpp

@@ -180,6 +180,10 @@ void WorldBuilder::configure_starting_items(DinkyECS::World &world) {
   auto &inventory = world.get_the<inventory::Model>();
   inventory.add("hand_r", torch_id);
   world.make_constant(torch_id);
+
+  auto healing = System::spawn_item(world, "POTION_HEALING_SMALL");
+  inventory.add("hand_l", healing);
+  world.make_constant(healing);
 }
 
 void WorldBuilder::place_entities(DinkyECS::World &world) {