Add gremlin/io package export exposing GraphBinary serializers (#3511)

Assisted-by: Claude Code:claude-opus-4-8

Author: danielbodart

CHANGELOG.asciidoc

@@ -26,6 +26,7 @@ image::https://raw.githubusercontent.com/apache/tinkerpop/master/docs/static/ima
 === TinkerPop 4.0.0 (Release Date: NOT OFFICIALLY RELEASED YET)
 
 * Added GraphBinary `Tree` (`0x2b`) serialization and deserialization with a native tree-shaped API to `gremlin-python`, `gremlin-dotnet`, `gremlin-go`, and `gremlin-javascript`.
+* Added a `gremlin/io` package export in `gremlin-javascript` exposing the GraphBinary type serializers.
 * Raised the minimum Java version to 17 for building and running *(breaking)*.
 * Enabled building and running with Java 21 and Java 25.
 * Bumped Groovy to 4.0.32, Hadoop to 3.4.3, Spark to 4.1.2 (Scala 2.13), and Netty to 4.2.7 to support Java 25.

gremlin-js/gremlin-javascript/package.json

@@ -33,6 +33,10 @@
     "./language": {
       "import": "./build/esm/language/index.js",
       "types": "./build/esm/language/index.d.ts"
+    },
+    "./io": {
+      "import": "./build/esm/structure/io/binary/GraphBinary.js",
+      "types": "./build/esm/structure/io/binary/GraphBinary.d.ts"
     }
   },
   "typesVersions": {