mermaid-authoring

Run `npx skills use "https://github.com/aretw0/agents-lab" --skill "aretw0/agents-lab/mermaid-authoring"` 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/aretw0/agents-lab" that are relevant to the current task. Run `npx skills add "https://github.com/aretw0/agents-lab"` and select the relevant skills, then follow their instructions.