fix: activity bar examples - #371

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/cache@v4, actions/upload-artifact@v4. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

Unexpected input(s) 'cache', valid inputs are ['bun-version', 'bun-version-file', 'bun-download-url', 'registries', 'registry-url', 'scope', 'no-cache', 'token']

Unexpected input(s) 'cache', valid inputs are ['bun-version', 'bun-version-file', 'bun-download-url', 'registries', 'registry-url', 'scope', 'no-cache', 'token']