feat(r2): 阶段3 页面数据源切换到服务端 API（失败降级本地缓存）

- designList：列表/批量删除走 API，新增生产中(processing)徽标与筛选 tab
- address：增删改查走 API，默认唯一性由服务端事务保证
- product：加入清单走 createDesign（服务端 DRAFT）
- diy：进入即创建清单条目；保存时 category 裁剪 {id,mask,tone}、
  designData 与服务端数据合并（保护 wordcloud 分组，WCD 红线）、
  贴纸经 persistDesignMedia 持久化后整包提交（状态→designing）
- stickerEdit：贴纸编辑合并后整包提交
- types：DesignDataV1.category 收窄为契约 §2 冻结形状 {id, mask, tone}
- 全部写入点：API 成功回写本地缓存（checkout 等未迁移页面不受影响）

Co-Authored-By: Claude <noreply@anthropic.com>

src/pages/diy/index.tsx

@@ -4,7 +4,7 @@ import { useState, useEffect } from 'react'
 import './index.scss'
 import { getProductById } from '../../utils/productConfig'
 import { getDesignList, setDesignList, updateDesign, type DesignItem, type StickerItem } from '../../utils/store'
-import { persistDesignMedia } from '../../utils/api'
+import { createDesign, updateDesign as updateDesignApi, persistDesignMedia } from '../../utils/api'
 import { useThemeContext } from '../../context/ThemeContext'
 import { useSafeArea } from '../../hooks/useSafeArea'
 import { useStatusBar } from '../../hooks/useStatusBar'
@@ -27,6 +27,34 @@ export default function DIYPage() {
   const [previewMode, setPreviewMode] = useState(false)
   const [hasOverlap, setHasOverlap] = useState(false)
 
+  /** 进入 DIY 即创建清单条目：服务端创建（DRAFT，阶段0 决策#6），失败降级本地 */
+  const createDesignEntry = (product: { id: string; name: string; price: number; icon: string }, count: number) => {
+    createDesign({
+      productId: product.id,
+      productName: product.name,
+      unitPrice: product.price,
+      count
+    })
+      .then(item => {
+        setDesignList([item, ...getDesignList()]) // 回写缓存，checkout 等页面仍读缓存
+        setDesignId(item.id)
+      })
+      .catch(() => {
+        const newDesign: DesignItem = {
+          id: 'DSG' + Date.now(),
+          productId: product.id,
+          productName: product.name,
+          productIcon: product.icon,
+          unitPrice: product.price,
+          count,
+          status: 'undesigned',
+          createdAt: new Date().toISOString().slice(0, 10)
+        }
+        setDesignList([...getDesignList(), newDesign])
+        setDesignId(newDesign.id)
+      })
+  }
+
   useEffect(() => {
     const router = Taro.getCurrentInstance().router
     const params = router ? router.params : undefined
@@ -37,20 +65,9 @@ export default function DIYPage() {
       const product = getProductById(productId)
       if (product) {
         setCategory(product)
-        setQuantity(Number(params ? params.quantity : undefined) || 1)
-        const newDesign: DesignItem = {
-          id: 'DSG' + Date.now(),
-          productId: product.id,
-          productName: product.name,
-          productIcon: product.icon,
-          unitPrice: product.price,
-          count: Number(params ? params.quantity : undefined) || 1,
-          status: 'designing',
-          createdAt: new Date().toISOString().slice(0, 10)
-        }
-        const list = getDesignList()
-        setDesignList([...list, newDesign])
-        setDesignId(newDesign.id)
+        const count = Number(params ? params.quantity : undefined) || 1
+        setQuantity(count)
+        createDesignEntry(product, count)
       }
       return
     }
@@ -89,19 +106,7 @@ export default function DIYPage() {
       const found = getProductById(productId)
       if (found) {
         setCategory(found)
-        const newDesign: DesignItem = {
-          id: 'DSG' + Date.now(),
-          productId: found.id,
-          productName: found.name,
-          productIcon: found.icon,
-          unitPrice: found.price,
-          count: 1,
-          status: 'designing',
-          createdAt: new Date().toISOString().slice(0, 10)
-        }
-        const list = getDesignList()
-        setDesignList([...list, newDesign])
-        setDesignId(newDesign.id)
+        createDesignEntry(found, 1)
       }
     }
   }, [])
@@ -247,10 +252,39 @@ export default function DIYPage() {
       Taro.showToast({ title: '贴纸不能重叠', icon: 'none' })
       return
     }
-    if (designId) {
+    if (designId && category) {
       // 贴纸/底图持久化（决策#4，R4 负责）：本地图 → COS 持久 URL，保证后端 WCD 打包可下载素材
       const data = await persistDesignMedia({ stickers, category, version: 1 })
-      updateDesign(designId, { designData: data })
+      // category 裁剪为 {id, mask, tone}（阶段0 决策#2；契约约束#3：mask 必须保留）
+      const trimmedCategory = {
+        id: category.id,
+        mask: category.mask,
+        ...(category.tone ? { tone: category.tone } : {})
+      }
+      // WCD 红线：基于服务端已有 designData 合并（保留 R4 写入的 wordcloud 分组等），只覆盖本页编辑的字段
+      const cached = getDesignList().find(d => d.id === designId)
+      const designData = {
+        ...(cached && cached.designData ? cached.designData : {}),
+        version: 1 as const,
+        category: trimmedCategory,
+        stickers: data.stickers || stickers
+      }
+      // 本地缓存同步（checkout 仍读缓存）
+      updateDesign(designId, { status: 'designing', designData })
+      try {
+        await updateDesignApi(designId, {
+          status: 'designing',
+          item: {
+            productId: category.id,
+            productName: category.name,
+            unitPrice: category.price,
+            count: quantity,
+            designData
+          }
+        })
+      } catch {
+        Taro.showToast({ title: '网络不可用，已暂存到本地', icon: 'none' })
+      }
     }
     setPreviewMode(false)
     Taro.navigateTo({ url: `/pages/checkout/index?designId=${designId}` })