chore: seal Design Vision v1 and monorepo scaffold

Archive the differentiated YuXinGu product docs, AI engineering system,
design contract, and Go/Vue scaffold. Next execution prioritizes Cece-parity
over early innovation (see .ai/product/STRATEGY.md).

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

.ai/ui.md

@@ -0,0 +1,64 @@
+# UI — Product chrome + pointer to Design Contract
+
+**Visual / component rules:** `.ai/design/design-system.md` (mandatory before UI work).  
+**Catalog:** `.ai/design/component-catalog.md`  
+**Platform:** `.ai/design/platform/h5.md` (default) · `mini-program.md` · `website.md` · `flutter.md`
+
+---
+
+## Brand (summary)
+
+- Primary `#E54D42` → `--color-primary` / `--yxg-pri`
+- Atmosphere: peach wash → white sheet
+- Mobile-first; user column ~430px
+- Unicode symbols over emoji in chrome
+
+---
+
+## H5 structure
+
+```
+apps/user-h5/src/
+  pages/
+  components/
+  layouts/
+  hooks/
+  api/
+  stores/
+  router/
+  assets/
+```
+
+No raw `fetch` in `pages/`. Tokens from `packages/ui`.
+
+---
+
+## Tabs (product IA)
+
+Home / Explore / **Ask** / Companion / Mine.  
+Ask is the strategic center tab.
+
+---
+
+## Copy / compliance
+
+- No medical cure claims
+- No 吉凶祸福
+- Report screens include disclaimer
+- Brand voice: see design-system §13
+
+---
+
+## Interaction
+
+- One job per section
+- Home first viewport: brand, decode entry, then content sheet
+- Loading / empty / error required for network views
+
+---
+
+## Mini program
+
+- Own `components/`; share tokens from `packages/ui`, not Vue SFCs
+- Pages → `services/*` only
+- See `design/platform/mini-program.md`