secondary-material-builder

Run `npx skills use "https://github.com/pblsketch/k-teacher-skills" --skill "pblsketch/k-teacher-skills/secondary-material-builder"` and follow the generated skill instructions now. Read its complete output, redirecting it to a temporary file first if necessary. Resolve relative paths from the supporting-files directory it provides.

Use the skills in "https://github.com/pblsketch/k-teacher-skills" that are relevant to the current task. Run `npx skills add "https://github.com/pblsketch/k-teacher-skills"` and select the relevant skills, then follow their instructions.