CI Node version pinning across workflows

Pin exact Node patch versions in a workflow-level env: block; floating majors can remain cached after security fixes. Current pins are NODE_VERSION_22="22.23.1" and NODE_VERSION_24="24.18.0". Reference ${{ env.NODE_VERSION_22 }} directly. Matrix labels remain bare majors for readable job names and select the pin with ${{ matrix.node == '24' && env.NODE_VERSION_24 || env.NODE_VERSION_22 }}. Apply the centralized pattern to ci.yml, release.yml, sentry-release.yml, and docs-preview.yml. eval-skill-fork.yml has no setup-node step, so add one explicitly when pinning it.