🐛 fix(skills): remove dual-path from commit-message skill

Drop the vendoring-scenario fallback path from commit-message/SKILL.md.
rewrite_skill_docs_links handles path rewriting at install time, so the
source file only needs the canonical docs/common/ path.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

codex/skills/commit-message/SKILL.md

@@ -11,11 +11,9 @@ description:
 目标：基于 `git diff --cached`（staged
 diff）生成 1–3 条提交信息建议：`:emoji: type(scope): subject`（可选 body/footer）。
 
-权威规范（单一真源，优先就近路径）：
+权威规范（单一真源）：
 
 - `docs/common/commit_message.md`
-- `docs/standards/playbook/docs/common/commit_message.md`（Playbook
-  vendoring 场景）
 
 ## When to use