feat(ecommerce): use FormData binary upload instead of base64 dataUrl

- Add uploadAssetBinary method to aiGenerationClient (FormData + busboy)
- Replace base64 dataUrl upload in uploadProductImages with direct blob upload
  via /oss/upload-binary multipart endpoint
- This eliminates the DATA_URL_PATTERN regex parsing bug that produced
  44-byte corrupt files on OSS, causing DashScope "image format illegal" errors

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/features/ecommerce/EcommercePage.tsx

@@ -1326,15 +1326,10 @@ function ProductClonePage(_props: ProductClonePageProps = {}) {
     for (const item of productImages) {
       try {
         const resp = await fetch(item.src);
-        const blob = await resp.blob();
-        const mimeType = SUPPORTED_IMAGE_TYPES.has(blob.type) ? blob.type : "image/png";
-        const dataUrl = await new Promise<string>((resolve, reject) => {
-          const reader = new FileReader();
-          reader.onload = () => resolve(String(reader.result));
-          reader.onerror = () => reject(reader.error);
-          reader.readAsDataURL(blob);
-        });
-        const { url } = await aiGenerationClient.uploadAsset({ dataUrl, name: item.name, mimeType });
+        const rawBlob = await resp.blob();
+        const mimeType = SUPPORTED_IMAGE_TYPES.has(rawBlob.type) ? rawBlob.type : "image/png";
+        const blob = rawBlob.type === mimeType ? rawBlob : new Blob([rawBlob], { type: mimeType });
+        const { url } = await aiGenerationClient.uploadAssetBinary(blob, { name: item.name, mimeType, scope: "ecommerce-product" });
         urls.push(url);
       } catch {
         // skip images that fail to upload