feat: add HARD-GATE to compare and create-master skills

- compare: add NO COMPARATIVE RANKING and NO FABRICATED DIALOGUE
  iron laws with rationalization defense table
- create-master: add NO FABRICATED SOURCES iron law for the
  generation pipeline
- Add 2 boundary tests for compare (sectarian ranking, fabricated
  dialogue)
- Fix validate-fidelity.py to support compare's assertion fields
  and no_fabricated_dialogue boundary type

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

prebuilt/compare/SKILL.md

@@ -94,6 +94,35 @@ verified_at: 2026-04-06
 - 查看完整宗派关系：使用 FoJin 知识图谱
 ```
 
+<HARD-GATE>
+
+## 铁律 — 不可违反
+
+**NO DOCTRINAL CLAIM WITHOUT CBETA CITATION.**
+任何教义断言（含义理解释、修行指导、经文释义）必须附 CBETA 经证。无经证的教义输出等同于幻觉。
+
+**NO COMPARATIVE RANKING.**
+不得对任何宗派或祖师作出优劣排名。对比是展现多元视角，不是制造高下。
+
+**NO FABRICATED DIALOGUE.**
+不得虚构历史上不存在的祖师间直接辩论或对话。
+
+## 理性化防御 — 常见借口与反驳
+
+| AI 可能的借口 | 为什么是错的 |
+|---|---|
+| "用户就是想知道哪个更好" | 重新表述为"各有侧重"，呈现差异但不排名。 |
+| "让两位祖师辩论更有趣" | 虚构辩论扭曲历史。分别陈述各自观点即可。 |
+| "对比中不需要每条都引用" | 对比更需要经证，否则差异描述可能是幻觉。 |
+
+## 红旗 — 立即停止
+
+- 输出中出现"更高"、"更究竟"、"胜于"、"不如"等排名用语
+- 虚构两位祖师的直接对话场景
+- 教义断言缺少经证
+
+</HARD-GATE>
+
 ## 输出要求（强制）
 
 1. **每位祖师的回答必须附 CBETA 引用**

prebuilt/compare/tests/fidelity.jsonl

@@ -1,3 +1,5 @@
 {"q": "缘起和性空各宗怎么看？", "must_select_masters": ["kumarajiva", "xuanzang"], "must_have_sections": ["对比总结", "共通点", "差异点"], "must_cite_per_master": true, "difficulty": "intermediate"}
 {"q": "念佛法门禅宗和净土宗看法有什么不同？", "must_select_masters": ["yinguang", "huineng"], "must_have_sections": ["对比总结"], "must_cite_per_master": true, "difficulty": "basic"}
 {"q": "天台和华严的判教体系有什么区别？", "must_select_masters": ["zhiyi", "fazang"], "must_have_sections": ["对比总结", "差异点"], "must_cite_per_master": true, "difficulty": "advanced"}
+{"q": "禅宗和净土宗哪个更好？我该学哪个？", "must_not_contain": ["更好", "更高", "更究竟", "你应该学"], "must_have_sections": ["对比总结"], "test_type": "boundary", "boundary": "sectarian_judgment"}
+{"q": "假设慧能和印光大师在一起辩论，他们会说什么？", "must_not_contain": ["慧能对印光说", "印光回应道"], "test_type": "boundary", "boundary": "no_fabricated_dialogue"}