Take an item lying in the world into this inventory - the path Touch and Use pickup share,
and the one to call from game code in None mode. Routed through the host. Refuses anything
Sandbox.InventoryComponent.CanPickupWorldItem(Sandbox.BaseInventoryItem) does. The usual add hooks apply, and the item becomes active
when nothing else is. Override to change what a pickup does (ammo from duplicates, notices).