Add method to access owner

Makes handling ISpecialInventory ownership much more consistent with a lot less spaghetti.

plugin/src/main/java/com/lishid/openinv/internal/OpenInventoryView.java

@@ -17,7 +17,6 @@
 package com.lishid.openinv.internal;
 
 import com.lishid.openinv.OpenInv;
-import java.util.Objects;
 import org.bukkit.entity.HumanEntity;
 import org.bukkit.entity.Player;
 import org.bukkit.event.inventory.InventoryType;
@@ -63,7 +62,7 @@ public class OpenInventoryView extends InventoryView {
     @Override
     public @NotNull String getTitle() {
         if (title == null) {
-            HumanEntity owner = (HumanEntity) Objects.requireNonNull(inventory.getBukkitInventory().getHolder());
+            HumanEntity owner = inventory.getPlayer();
 
             String localTitle = OpenInv.getPlugin(OpenInv.class)
                     .getLocalizedMessage(

plugin/src/main/java/com/lishid/openinv/listeners/InventoryListener.java

@@ -199,7 +199,7 @@ public class InventoryListener implements Listener {
         }
 
         // Only specially handle actions in the player's own inventory.
-        return !event.getWhoClicked().equals(event.getView().getTopInventory().getHolder());
+        return !event.getWhoClicked().equals(playerInventory.getPlayer());
     }
 
 }