Records the upstream agentskills.io sources that informed skill-author,
completing the research → docs → skill provenance chain introduced in
the previous commit.
- New references/sources.md with all 7 extracted agentskillsio sources,
Contributing files attributed per-source to SKILL.md, references/deployment-modes.md,
and references/scripts.md
- source_keys frontmatter added to SKILL.md (all 7 slugs), references/deployment-modes.md
(agentskills-spec), and references/scripts.md (agentskills-using-scripts)
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>