Remove compile time linkage in favour of class index

Optimize build time when no change happened for the BauSystem

BauSystem/BauSystem_Main/src/de/steamwar/bausystem/features/gui/BauGUI.java

@@ -23,9 +23,9 @@ import de.steamwar.bausystem.BauSystem;
 import de.steamwar.bausystem.Permission;
 import de.steamwar.bausystem.SWUtils;
 import de.steamwar.bausystem.features.gui.editor.BauGuiMapping;
-import de.steamwar.bausystem.linkage.LinkageUtils;
 import de.steamwar.bausystem.linkage.specific.BauGuiItem;
 import de.steamwar.inventory.SWInventory;
+import lombok.Getter;
 import lombok.experimental.UtilityClass;
 import net.md_5.bungee.api.ChatColor;
 import org.bukkit.Material;
@@ -38,13 +38,9 @@ import java.util.*;
 @UtilityClass
 public class BauGUI {
 
+    @Getter
     private static final Map<Integer, BauGuiItem> ITEMS = new HashMap<>();
 
-    public static Map<Integer, BauGuiItem> getITEMS() {
-        if (ITEMS.isEmpty()) LinkageUtils.linkGUIItems();
-        return ITEMS;
-    }
-
     private static final Set<Player> OPEN_INVS = new HashSet<>();
     private static boolean updating = false;