Initial plan for reference implementation sync (2026-04-30)

Agent-Logs-Url: https://github.com/github/copilot-sdk-java/sessions/a61a1c47-9550-486c-800b-6deeeadaadbf

Co-authored-by: edburns <75821+edburns@users.noreply.github.com>

Author: Copilot

scripts/codegen/package-lock.json

@@ -7,7 +7,7 @@
     "generate:java": "tsx java.ts"
   },
   "dependencies": {
-    "@github/copilot": "^1.0.39",
+    "@github/copilot": "^1.0.40-0",
     "json-schema": "^0.4.0",
     "tsx": "^4.20.6"
   }