fix(ci): use npm ci against lockfile in promote workflow

The promote workflow ran `yarn install --frozen-lockfile`, but there is no
yarn.lock in the repo, so yarn resolved dependencies fresh and pulled a newer
@types/node whose ffi.d.ts the build's TypeScript parser cannot handle. This
broke the v6.6.0 and v6.7.0 promotions. Switch to `npm ci && npm run build`
so promotion uses the same pinned dependency set (package-lock.json) as the
release and PR build workflows.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: dlabaj

.github/workflows/promote.yml

@@ -13,12 +13,12 @@ jobs:
       NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
     steps:
       - uses: actions/checkout@v4
-      - name: Build for promotion
-        run: yarn install --frozen-lockfile && yarn build
       - uses: actions/setup-node@v4
         with:
           node-version: '20.x'
           registry-url: 'https://registry.npmjs.org'
+      - name: Build for promotion
+        run: npm ci && npm run build
       - name: GitHub Tag Name example
         run: |
           echo "Tag name from GITHUB_REF_NAME: $GITHUB_REF_NAME"