Fix publish workflow caching for per-package pnpm lockfiles

[Copilot]

The publish GitHub Actions job was failing because pnpm caching was still configured as if the repo had a root pnpm-lock.yaml. This repo installs and builds packages independently, so the workflow now keys caching off the per-package lockfiles instead.

• Root cause

  • actions/setup-node was using cache: pnpm without a dependency path override, which made it require /pnpm-lock.yaml at the repository root.
  • That conflicts with this repo’s package layout, where each tool owns its own lockfile.

• Workflow changes

  • Pin pnpm/action-setup to the repo’s pnpm version (11.15.1) for consistency with other workflows.
  • Update actions/setup-node to use all package lockfiles for pnpm cache invalidation:

    - uses: actions/setup-node@v4
      with:
        node-version: 22
        cache: pnpm
        cache-dependency-path: |
          **/pnpm-lock.yaml

  • Add a separate actions/cache entry for package-local node_modules directories so publish can benefit from per-package install reuse without reintroducing a root lockfile.

• Behavioral impact

  • The publish workflow no longer assumes a root lockfile exists.
  • Cache keys now track the actual package boundaries in this repository, including the nested tasks/src/in-the-cloud package.