Proxy Meshy GLB download through backend to bypass CORS

backend/server.js

@@ -531,7 +531,32 @@ app.get('/api/sparkplug/status-3d/:taskId', authenticate, async (req, res) => {
       }
     });
 
-    res.json(response.data);
+    const data = response.data;
+    
+    // If generation succeeded, intercept and proxy download the model to local storage to bypass CORS
+    if (data.status === 'SUCCEEDED' && data.model_urls && data.model_urls.glb) {
+      const glbUrl = data.model_urls.glb;
+      const localFilename = `${taskId}.glb`;
+      const localFilepath = path.join(uploadsDir, localFilename);
+      
+      // Only download if we haven't already
+      if (!fs.existsSync(localFilepath)) {
+        try {
+          const fileRes = await axios.get(glbUrl, { responseType: 'arraybuffer' });
+          fs.writeFileSync(localFilepath, fileRes.data);
+        } catch (downloadErr) {
+          console.error("Failed to proxy download Meshy GLB:", downloadErr);
+        }
+      }
+      
+      if (fs.existsSync(localFilepath)) {
+        // Overwrite the returned url with our local proxy url
+        const serverUrl = `${req.protocol}://${req.get('host')}`;
+        data.model_urls.glb = `${serverUrl}/uploads/${localFilename}`;
+      }
+    }
+
+    res.json(data);
   } catch (err) {
     const errorMsg = err.response?.data?.message || err.message;
     res.status(500).json({ error: errorMsg });