The site build fails on main #52

Summary

The Astro build on main stops with "Missing 'default' export" from js-yaml, so the site and its image do not build.

The new pull request check skips the build and the image build until this is fixed, and runs install and lint only. Pull request #46 proposes a fix.

Acceptance criteria

• The site and its image build on main, and the build check runs both again

Related to #50