Add a method on InventoryView to get the MenuType (#12193)

Since there is a new (better) way to create views for players using MenuType, it would be nice to also be able to get it back from InventoryView after creating.

paper-server/src/main/java/org/bukkit/craftbukkit/inventory/CraftContainer.java

@@ -95,6 +95,11 @@ public class CraftContainer extends AbstractContainerMenu {
                 this.title = title;
             }
 
+            @Override
+            public MenuType getMenuType() {
+                return CraftMenuType.minecraftToBukkit(getNotchInventoryType(inventory));
+            }
+
         }, player, id);
     }
 

paper-server/src/main/java/org/bukkit/craftbukkit/inventory/CraftInventoryView.java

@@ -94,6 +94,12 @@ public class CraftInventoryView<T extends AbstractContainerMenu, I extends Inven
         this.title = title;
     }
 
+    @Override
+    public org.bukkit.inventory.MenuType getMenuType() {
+        MenuType<?> menuType = container.menuType;
+        return menuType != null ? CraftMenuType.minecraftToBukkit(menuType) : null;
+    }
+
     public boolean isInTop(int rawSlot) {
         return rawSlot < this.viewing.getSize();
     }