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-share-detail/outfit-share-detail.wxml

@@ -38,7 +38,7 @@ module.exports = { cls: cls }
 
     <view class="osd-owner">
       <view class="osd-av">
-        <image wx:if="{{detail.owner_avatar}}" class="pic" src="{{detail.owner_avatar}}" mode="aspectFill" />
+        <cached-image wx:if="{{detail.owner_avatar}}" class="pic" src="{{detail.owner_avatar}}" mode="aspectFill" />
         <view wx:else class="icon icon-user"></view>
       </view>
       <view class="osd-owner-body">
@@ -51,7 +51,7 @@ module.exports = { cls: cls }
     <view class="osd-cover">
       <view class="collage {{cl.cls(outfit.items.length)}}">
         <view class="cg" wx:for="{{outfit.items}}" 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="{{outfit.items.length > 4}}" class="cg-more">+{{outfit.items.length - 4}}</view>
@@ -84,7 +84,7 @@ module.exports = { cls: cls }
             bindtap="onItemTap"
           >
             <view class="osd-thumb">
-              <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>