docs(readme): drop misattributed "borrowing from" in Quality gates

Both attributions were wrong:

- Structural validation was credited to "Codex skill-creator" at
  github.com/openai/skills — but that repo has no skill-creator, and
  validator.py is explicitly modeled on Anthropic's quick_validate.py
  (see the module docstring).
- Trigger-accuracy evals were credited to Anthropic skill-creator —
  but evaluator.py has no such inspiration in its docstrings; the
  design (description-only trigger grader + body-aware coverage
  grader) is OpenKB's own.

Iteration pattern in workspace.py is genuinely borrowed from Anthropic
skill-creator, and that credit lives in the module docstring where it
belongs.

Reframed the README line to describe what the gates do, without
parading non-existent or backwards lineage.

Author: KylinMountain

README.md

@@ -243,7 +243,7 @@ npx skills@latest add <your-org>/<your-repo>
 [agent edits SKILL.md frontmatter in place]
 ```
 
-**Quality gates** — borrowing from [Codex skill-creator](https://github.com/openai/skills) (structural validation) and [Anthropic skill-creator](https://github.com/anthropics/skills/tree/main/skills/skill-creator) (trigger-accuracy evals):
+**Quality gates** — structural validation, trigger-accuracy + body-coverage evaluation, and full history/rollback:
 
 ```bash
 # Lint structure (auto-runs at end of `skill new`)