style(checkout): 消除 previewStickers 链式调用的隐式 any

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

src/pages/checkout/index.tsx

@@ -119,11 +119,11 @@ export default function CheckoutPage() {
   }
 
   // 图层顺序与 WCD 打包规则一致（按 zIndex，无 zIndex 按数组序兜底）
-  const previewStickers = hasStickers
+  const previewStickers: any[] = hasStickers
     ? design.designData!.stickers!
         .map((s: any, i: number) => ({ s, z: typeof s.zIndex === 'number' ? s.zIndex : i }))
-        .sort((a, b) => a.z - b.z)
-        .map((it) => it.s)
+        .sort((a: { z: number }, b: { z: number }) => a.z - b.z)
+        .map((it: { s: any }) => it.s)
     : []
 
   const formatAddress = (region: string[] | undefined, detail: string) => {