fix(ext/node): emit Buffer for http2 'goaway' opaqueData (#33502)

Enables `test-http2-goaway-opaquedata` in node_compat suite.

Co-authored-by: divybot <divybot@users.noreply.github.com>
Co-authored-by: Divy Srivastava <me@littledivy.com>

Author: divybot

ext/node/polyfills/http2.ts

@@ -781,7 +781,13 @@ function onGoawayData(code, lastStreamID, buf) {
   state.goawayCode = code;
   state.goawayLastStreamID = lastStreamID;
 
-  session.emit("goaway", code, lastStreamID, buf);
+  // Node.js exposes the GOAWAY opaque data as a Buffer, not a plain
+  // Uint8Array. The native binding hands us a Uint8Array, so wrap it
+  // as a Buffer (zero-copy) before emitting.
+  const opaqueData = buf !== undefined
+    ? Buffer.from(buf.buffer, buf.byteOffset, buf.byteLength)
+    : buf;
+  session.emit("goaway", code, lastStreamID, opaqueData);
   if (code === NGHTTP2_NO_ERROR) {
     // If this is a no error goaway, begin shutting down.
     // No new streams permitted, but existing streams may

tests/node_compat/config.jsonc

@@ -1496,6 +1496,7 @@
     "parallel/test-http2-error-order.js": {},
     "parallel/test-http2-getpackedsettings.js": {},
     "parallel/test-http2-goaway-delayed-request.js": {},
+    "parallel/test-http2-goaway-opaquedata.js": {},
     "parallel/test-http2-graceful-close.js": {},
     "parallel/test-http2-head-request.js": {},
     "parallel/test-http2-info-headers.js": {},