refreshAll

Refreshes all registered GUIs that are associated with this virtual inventory, prompting them to update their display to reflect the current state of the inventory. This method can be called after making multiple changes to the inventory to ensure that all GUIs are updated at once, rather than refreshing each GUI individually for every change. It iterates through all registered GUIs and calls their refreshVirtualInventory method with the corresponding inventoryId, allowing them to update their display based on the latest state of the virtual inventory.