Finished adding confirm button

Fixed controlling gui from player inventory

src/main/java/com/alttd/objects/Purchase.java

@@ -0,0 +1,6 @@
+package com.alttd.objects;
+
+import org.bukkit.Material;
+
+public record Purchase(Material material, double price, int singlePointCost, int totalPointCost, int amount) {
+}