feature(nbt): CompoundBinaryTag#createBuilder

nbt/src/main/java/net/kyori/adventure/nbt/CompoundBinaryTag.java

@@ -154,6 +154,14 @@ public interface CompoundBinaryTag extends BinaryTag, CompoundTagSetter<Compound
     return BinaryTagTypes.COMPOUND;
   }
 
+  /**
+   * Creates a builder, pre-filled with the contents of this compound.
+   *
+   * @return a new builder
+   * @since 4.24.0
+   */
+  Builder createBuilder();
+
   /**
    * Gets a set of all keys.
    *

nbt/src/main/java/net/kyori/adventure/nbt/CompoundBinaryTagImpl.java

@@ -53,6 +53,11 @@ public boolean contains(final @NotNull String key, final @NotNull BinaryTagType<
     return tag != null && type.test(tag.type());
   }
 
+  @Override
+  public Builder createBuilder() {
+    return new CompoundTagBuilder(new HashMap<>(this.tags)); // explicitly copy
+  }
+
   @Override
   public @NotNull Set<String> keySet() {
     return Collections.unmodifiableSet(this.tags.keySet());

nbt/src/main/java/net/kyori/adventure/nbt/CompoundTagBuilder.java

@@ -32,6 +32,13 @@
 final class CompoundTagBuilder implements CompoundBinaryTag.Builder {
   private @Nullable Map<String, BinaryTag> tags;
 
+  CompoundTagBuilder() {
+  }
+
+  CompoundTagBuilder(final Map<String, BinaryTag> tags) {
+    this.tags = tags;
+  }
+
   private Map<String, BinaryTag> tags() {
     if (this.tags == null) {
       this.tags = new HashMap<>();