Fix a couple of ItemMeta related NPEs (#11149)

patches/server/Adventure.patch

@@ -4927,15 +4927,13 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 +
 +    @Override
 +    public net.kyori.adventure.text.Component page(final int page) {
-+        Preconditions.checkArgument(this.isValidPage(page), "Invalid page number");
++        Preconditions.checkArgument(this.isValidPage(page), "Invalid page number (%s/%s)", page, this.getPageCount());
 +        return net.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer.legacySection().deserialize(this.pages.get(page - 1));
 +    }
 +
 +    @Override
 +    public void page(final int page, net.kyori.adventure.text.Component data) {
-+        if (!this.isValidPage(page)) {
-+            throw new IllegalArgumentException("Invalid page number " + page + "/" + this.pages.size());
-+        }
++        Preconditions.checkArgument(this.isValidPage(page), "Invalid page number (%s/%s)", page, this.getPageCount());
 +        if (data == null) {
 +            data = net.kyori.adventure.text.Component.empty();
 +        }
@@ -5120,15 +5118,13 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 +
 +    @Override
 +    public net.kyori.adventure.text.Component page(final int page) {
-+        Preconditions.checkArgument(this.isValidPage(page), "Invalid page number");
++        Preconditions.checkArgument(this.isValidPage(page), "Invalid page number (%s/%s)", page, this.getPageCount());
 +        return io.papermc.paper.adventure.PaperAdventure.asAdventure(this.pages.get(page - 1));
 +    }
 +
 +    @Override
 +    public void page(final int page, net.kyori.adventure.text.Component data) {
-+        if (!this.isValidPage(page)) {
-+            throw new IllegalArgumentException("Invalid page number " + page + "/" + this.pages.size());
-+        }
++        Preconditions.checkArgument(this.isValidPage(page), "Invalid page number (%s/%s)", page, this.getPageCount());
 +        this.pages.set(page - 1, io.papermc.paper.adventure.PaperAdventure.asVanillaNullToEmpty(data));
 +    }
 +

patches/server/General-ItemMeta-fixes.patch

@@ -71,6 +71,16 @@ diff --git a/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java
 index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
 --- a/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java
 +++ b/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java
+@@ -0,0 +0,0 @@ public final class CraftItemStack extends ItemStack {
+ 
+     @Override
+     public void removeEnchantments() {
++        if (this.handle != null) { // Paper - fix NPE
+         this.handle.remove(DataComponents.ENCHANTMENTS);
++        } // Paper
+     }
+ 
+     @Override
 @@ -0,0 +0,0 @@ public final class CraftItemStack extends ItemStack {
      // Paper end - improve handled tags on type change
      // Paper start