Fix Mass Opening Crates causing TPS Drops

src/main/java/su/nightexpress/excellentcrates/opening/inventory/spinner/AbstractSpinner.java

@@ -100,15 +100,13 @@ public void tick() {
     public void tickAll() {
         if (!this.running) return;
 
-        long total = Math.max(0L, this.getTotalSpins());
-
-        for (int count = 0; count < total; count++) {
-            if (this.isCompleted()) break;
-
-            this.onSpin();
-        }
+        // Instant openings are closed immediately, so there is no reason
+        // to render every invis animation frame.
+        this.spinCount = Math.max(1L, this.requiredSpins);
+        this.steps.clear();
+        this.currentStep = null;
     }
-
+    
     @Override
     public boolean isSpinTime() {
         if (this.spinDelay > 0) {

src/main/java/su/nightexpress/excellentcrates/opening/inventory/spinner/impl/RewardSpinner.java

@@ -14,7 +14,7 @@
 import su.nightexpress.excellentcrates.opening.inventory.spinner.SpinnerData;
 import su.nightexpress.nightcore.util.Lists;
 import su.nightexpress.nightcore.util.random.Rnd;
-
+import java.util.IdentityHashMap;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -23,7 +23,7 @@
 public class RewardSpinner extends AbstractSpinner {
 
     private final Set<Rarity> rarities;
-
+    private final Map<Reward, ItemStack> previewCache = new IdentityHashMap<>();
     private int rewardIndex;
 
     public RewardSpinner(@NotNull SpinnerData data, @NotNull InventoryOpening opening, @NotNull Set<Rarity> rarities) {
@@ -75,12 +75,23 @@ private Reward rollReward(boolean visual) {
     @Override
     @NotNull
     public ItemStack createItem(int slot) {
-        Reward reward = this.shouldUsePredictedReward(slot) ? this.opening.getRewards().get(this.rewardIndex++) : this.rollReward(true);
-        if (reward == null) return new ItemStack(Material.AIR);
+        Reward reward = this.shouldUsePredictedReward(slot)
+                ? this.opening.getRewards().get(this.rewardIndex++)
+                : this.rollReward(true);
+
+        if (reward == null) {
+            return new ItemStack(Material.AIR);
+        }
+
+        ItemStack preview = this.previewCache.computeIfAbsent(
+                reward,
+                Reward::getPreviewItem
+        );
 
-        return reward.getPreviewItem();
+        return preview.clone();
     }
 
+
     private boolean shouldUsePredictedReward(int slot) {
         if (this.rewardIndex >= this.opening.getRewards().size()) return false;
 

src/main/java/su/nightexpress/excellentcrates/util/ItemHelper.java

@@ -75,7 +75,7 @@ else if (adapter == null) {
 
     @NotNull
     public static ItemStack toItemStack(@NotNull AdaptedItem item) {
-        return item.itemStack().orElse(CrateUtils.getQuestionStack());
+        return item.itemStack().orElseGet(CrateUtils::getQuestionStack);
     }
 
     public static boolean isCustom(@NotNull ItemStack itemStack) {