Trigger CI for workflow config changes

[abewheel]

Summary

• Add workflow files to the CI path filters so CI config fixes start new runs.
• Add root package.json to the path filters because it defines the pnpm packageManager version.
• Run pnpm workflows on Node 22 so pnpm 11.7.0 has a supported runtime.

Testing

• Parsed .github/workflows/ci.yml and .github/workflows/publish.yml with Ruby YAML.
• Ran git diff --check.
• Ran pnpm validate; package install, format, lint, build, typecheck, unit tests, docs validation, package e2e, and example generation passed before the validation wrapper stopped emitting output during generated example tests.