feat(kyberforge): add skill-author, merging skill-write and skill-improve

Closes #5. Single authoring skill replaces the factory trio — one set of
standards, one script, one place for future governance rules. Routes to
create or improve flow based on context. Passes skill-audit with no findings.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016z2ZFYHQCex8yZAMVMTZzZ

plugins/kyberforge/skills/skill-author/assets/templates/references/README.md

@@ -0,0 +1,31 @@
+# references/
+
+Additional documentation agents load on demand. Files here extend SKILL.md
+without bloating its core context.
+
+## When to add a reference file
+
+Move content here when SKILL.md is approaching 500 lines, or when a topic
+is only relevant in specific circumstances (error handling, edge cases,
+domain-specific sub-procedures).
+
+## How to reference from SKILL.md
+
+Load conditionally — tell the agent exactly when to read each file:
+
+```markdown
+If the API returns a non-200 status, read `references/api-errors.md`.
+```
+
+Avoid generic "see references/ for details" — the agent loads context on
+demand, so give it a precise trigger condition.
+
+## File conventions
+
+- One topic per file — focused files mean less unnecessary context loaded
+- Kebab-case filenames (e.g. `api-errors.md`, `output-formats.md`)
+- Keep files under 200 lines where possible
+
+## If no reference files are needed
+
+Delete this README and the `references/` directory entirely.