Address review comments: node exit 0, pin setup-node SHA, update commit message

Agent-Logs-Url: https://github.com/github/copilot-sdk-java/sessions/a806a008-d6a9-4f91-9afd-746df3cc127a

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

Author: Copilot

.github/actions/setup-copilot/action.yml

@@ -10,7 +10,7 @@ outputs:
 runs:
   using: "composite"
   steps:
-    - uses: actions/setup-node@v6
+    - uses: actions/setup-node@60edb5dd545a775178f52524783378180af0d1f8 # v6
       with:
         node-version: 22
     - name: Read pinned @github/copilot version from pom.xml

.github/scripts/reference-impl-sync/merge-reference-impl-finish.sh

@@ -57,7 +57,7 @@ echo "▸ Syncing @github/copilot version in pom.xml from reference implementati
 "$ROOT_DIR/.github/scripts/reference-impl-sync/sync-cli-version-from-reference-impl.sh" "$REFERENCE_IMPL_DIR"
 
 git add .lastmerge pom.xml
-git commit -m "Update .lastmerge to $NEW_COMMIT"
+git commit -m "Update .lastmerge to $NEW_COMMIT and sync pom.xml CLI version"
 
 # ── 3. Push branch ───────────────────────────────────────────
 echo "▸ Pushing branch $BRANCH_NAME to origin…"

.github/scripts/reference-impl-sync/sync-cli-version-from-reference-impl.sh

@@ -56,7 +56,7 @@ fi
 
 # node is always available since the reference implementation uses npm.
 CLI_VERSION=$(node -e \
-    "const fs=require('fs');const p=JSON.parse(fs.readFileSync(process.argv[1],'utf8'));const v=(p.dependencies&&p.dependencies['@github/copilot'])||(p.devDependencies&&p.devDependencies['@github/copilot']);if(!v){process.exit(2);}process.stdout.write(v);" \
+    "const fs=require('fs');const p=JSON.parse(fs.readFileSync(process.argv[1],'utf8'));const v=(p.dependencies&&p.dependencies['@github/copilot'])||(p.devDependencies&&p.devDependencies['@github/copilot']);process.stdout.write(v||'');" \
     "$PKG_JSON")
 
 if [[ -z "$CLI_VERSION" ]]; then