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/assets/README.md

@@ -0,0 +1,29 @@
+# assets/
+
+Static resources bundled with this skill: templates, schemas, lookup tables,
+sample data, images.
+
+## When to add an asset
+
+Add a file here when the skill needs a static resource that:
+- Would be tedious to reproduce in instructions (a full JSON schema, a CSV
+  lookup table, a binary template)
+- Needs to be referenced by path rather than inlined in SKILL.md
+
+## How to reference from SKILL.md
+
+Use a relative path from the skill root:
+
+```markdown
+Use the schema at `assets/response-schema.json` to validate output.
+```
+
+Or instruct the agent to load it conditionally:
+
+```markdown
+If validating output format, use `assets/response-schema.json`.
+```
+
+## If no assets are needed
+
+Delete this README and the `assets/` directory entirely.