fix(ci): update npm to latest for trusted publishing OIDC support

npm >= 11.5.1 is required for trusted publishing to work correctly.
Node 22 ships with npm 10.x which causes E404 on OIDC publish.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: 2 people

.github/workflows/publish.yml

@@ -18,6 +18,7 @@ jobs:
         with:
           node-version: 22
           registry-url: 'https://registry.npmjs.org'
+      - run: npm install -g npm@latest
       - run: npm ci
       - run: npm run build
       - run: npm test