BE39: API Contract Alignment for Food & Scan Flows

[TienNguyen3711]

Summary

• restore the missing /api/fooddata/* lookup endpoints alongside the existing search endpoint
• clean up the food data controller so it only exposes the lookup handlers used by the food data routes
• accept barcode values from the request body so the backend matches the frontend barcode scan contract

What files changed

• routes/fooddata.js
• controller/foodDataController.js
• controller/barcodeScanningController.js

Testing

• node -c controller/foodDataController.js
• node -c controller/barcodeScanningController.js
• node -c routes/fooddata.js
• not run end-to-end