docs: freeze YuXinGu lexicon, journey, and P1 engineering sources

Establish product language contract, user journey with dual growth engines,
ERD/OpenAPI/Go boundaries, and H5 routes (/profile, /portrait, /relation,
/membership) before P1 implementation.

Co-authored-by: Cursor <cursoragent@cursor.com>

.ai/product/README.md

@@ -1,12 +1,13 @@
-# Product docs for AI agents
+# Product docs（AI 真源）
 
-| File | Audience | Purpose |
-|---|---|---|
-| [STRATEGY.md](STRATEGY.md) | All agents | **执行优先级**：先测测 parity，Vision v1 已封存 |
-| [feature-map.md](feature-map.md) | PRD / H5 / API | 愈心谷差异化能力树（Design Vision v1） |
-| [cece-feature-map.md](cece-feature-map.md) | Competitor / parity | 测测 Feature Tree — 下一版对齐主参考 |
-| [../domain/domain-map.md](../domain/domain-map.md) | Backend / DB / OpenAPI | Bounded contexts & entities |
-| [../domain.md](../domain.md) | All code | Ubiquitous language (terms only) |
+| File | Purpose |
+|---|---|
+| [ENGINEERING-FREEZE.md](ENGINEERING-FREEZE.md) | **P1 冻结清单** |
+| [lexicon.md](lexicon.md) | 产品语言契约（最高优先级） |
+| [feature-map.md](feature-map.md) | 能力树 · 五 Tab 冻结 |
+| [user-journey.md](user-journey.md) | 转化路径（含关系分享引擎） |
+| [page-tree.md](page-tree.md) | H5 路由树 |
+| [STRATEGY.md](STRATEGY.md) | 参考模型 ≠ 复制品牌 |
+| [cece-feature-map.md](cece-feature-map.md) | 竞品对照（勿抄 UI） |
 
-Product narrative docs (human PRD): `apps/docs/`.  
-**冲突时：** `STRATEGY.md` 的 parity 执行 > Vision v1 创新项。
+冲突：`lexicon` > `feature-map` / `user-journey` > 历史文档。