feat(image-cache): 新增图片本地缓存并全站接入

引入 cached-image 组件与 image-cache 工具，实现签名 URL 稳定 key 剥离、downloadFile 落盘及 TTL/LRU 清理，替换 11 个页面与 clothes-card 共 22 处网络图片渲染点，减少 CDN 重复流量。

miniprogram/pages/outfit-edit/outfit-edit.json

@@ -1,6 +1,7 @@
 {
   "usingComponents": {
     "navigation-bar": "/components/navigation-bar/navigation-bar",
+    "cached-image": "/components/cached-image/cached-image",
     "clothes-card": "/components/clothes-card/clothes-card",
     "v2-overlay": "/components/v2-overlay/index"
   }

miniprogram/pages/outfit-edit/outfit-edit.wxml

@@ -32,7 +32,7 @@ module.exports = { cls: cls }
         bindtap="openSelect"
       >
         <view class="cg" wx:for="{{selectedItems}}" wx:key="clothes_uuid" wx:if="{{index < 4}}">
-          <image wx:if="{{item.processed_image}}" class="pic" src="{{item.processed_image}}" mode="aspectFill" />
+          <cached-image wx:if="{{item.processed_image}}" class="pic" src="{{item.processed_image}}" mode="aspectFill" />
           <view wx:else class="ph icon icon-hanger"></view>
         </view>
         <view wx:if="{{selectedItems.length > 4}}" class="cg-more">+{{selectedItems.length - 4}}</view>