perf: read inventory holders without copying the block

src/main/java/net/tfminecraft/musicalinstruments/studio/StudioListener.java

@@ -129,7 +129,7 @@ public void breakBlock(BlockBreakEvent event) {
     @EventHandler(priority = EventPriority.HIGHEST, ignoreCancelled = true)
     public void hopper(InventoryMoveItemEvent event) {
         // Custom editions require our insertion lifecycle; vanilla discs retain hopper behavior.
-        if (studio.discs().custom(event.getItem()) && event.getDestination().getHolder() instanceof Jukebox) {
+        if (studio.discs().custom(event.getItem()) && event.getDestination().getHolder(false) instanceof Jukebox) {
             event.setCancelled(true);
         }
     }

src/main/java/net/tfminecraft/musicalinstruments/studio/StudioMenu.java

@@ -185,7 +185,7 @@ private ItemStack button(Material material, String title, NamedTextColor color,
 
     @EventHandler
     public void click(InventoryClickEvent event) {
-        if (!(event.getView().getTopInventory().getHolder() instanceof Holder holder)) return;
+        if (!(event.getView().getTopInventory().getHolder(false) instanceof Holder holder)) return;
         // Normal inventory clicks let the player pick up and put down the physical disc.
         if (event.getRawSlot() >= holder.inventory.getSize()
                 && (event.getClick() == ClickType.LEFT || event.getClick() == ClickType.RIGHT)) return;
@@ -312,7 +312,7 @@ private void refresh() {
 
     @EventHandler
     public void drag(InventoryDragEvent event) {
-        if (!(event.getView().getTopInventory().getHolder() instanceof Holder holder)) return;
+        if (!(event.getView().getTopInventory().getHolder(false) instanceof Holder holder)) return;
         if (event.getRawSlots().stream().noneMatch(slot -> slot < holder.inventory.getSize())) return;
         event.setCancelled(true);
         if (holder.screen == Screen.EDITOR && event.getRawSlots().equals(java.util.Set.of(50))
@@ -334,7 +334,7 @@ public void close() {
 
     // The holder of the player's open container; MockBukkit reports no top inventory when none is open.
     private static InventoryHolder open(Player player) {
-        return player.getOpenInventory().getTopInventory() instanceof Inventory top ? top.getHolder() : null;
+        return player.getOpenInventory().getTopInventory() instanceof Inventory top ? top.getHolder(false) : null;
     }
 
     private static final class Holder implements InventoryHolder {

src/test/java/net/tfminecraft/musicalinstruments/studio/StudioListenerTest.java

@@ -287,7 +287,7 @@
     void worldLifecycleAndHoppersRespectCustomRecordingPlayback() {
         listener.breakBlock(new org.bukkit.event.block.BlockBreakEvent(block, player));
         verify(studio).stop(block);
         listener.quit(new org.bukkit.event.player.PlayerQuitEvent(player, (net.kyori.adventure.text.Component) null));
         verify(studio).quit(player);
         var world = mock(org.bukkit.World.class);
         when(world.getUID()).thenReturn(java.util.UUID.randomUUID());
@@ -300,10 +300,10 @@
         verify(studio, times(2)).unload(world.getUID(), 2, 3);
         var source = mock(org.bukkit.inventory.Inventory.class);
         var destination = mock(org.bukkit.inventory.Inventory.class);
-        when(destination.getHolder()).thenReturn(box);
+        when(destination.getHolder(false)).thenReturn(box);
         var blocked = new org.bukkit.event.inventory.InventoryMoveItemEvent(source, disc, destination, true);
         listener.hopper(blocked); assertTrue(blocked.isCancelled());
-        when(destination.getHolder()).thenReturn(null);
+        when(destination.getHolder(false)).thenReturn(null);
         var ordinary = new org.bukkit.event.inventory.InventoryMoveItemEvent(source, disc, destination, true);
         listener.hopper(ordinary); assertFalse(ordinary.isCancelled());
         when(discs.custom(disc)).thenReturn(false);

src/test/java/net/tfminecraft/musicalinstruments/studio/StudioMenuTest.java

@@ -88,6 +88,7 @@ void setup() throws Exception {
         when(scheduler.runTaskTimer(eq(plugin), any(Runnable.class), eq(10L), eq(10L))).thenReturn(refreshTask);
         when(server.createInventory(any(InventoryHolder.class), anyInt(), any(Component.class))).thenAnswer(call -> {
             when(inventory.getHolder()).thenReturn(call.getArgument(0));
+            when(inventory.getHolder(false)).thenReturn(call.getArgument(0));
             when(inventory.getSize()).thenReturn(call.getArgument(1));
             return inventory;
         });