fix: strip EXIF from image blob in backend before processing

Backend receives the original blob which may have EXIF orientation metadata.
Strip it before processing to ensure backend analyzes the same raw image space
that Gemini analyzed (which had EXIF stripped before sending).

This ensures rotation_degrees are applied correctly to the same image state.

backend/routers/items.py

@@ -161,6 +161,10 @@ def create_item(
             image_bytes = base64.b64decode(item.extracted_image_bytes)
             log.info(f"[CREATE_ITEM] Received {len(image_bytes)} bytes for photo processing (base64 decoded)")
 
+            # Strip EXIF orientation to match what Gemini analyzed
+            image_bytes = strip_exif_orientation(image_bytes)
+            log.info(f"[CREATE_ITEM] After EXIF strip: {len(image_bytes)} bytes")
+
             photo_result = _auto_save_photo_from_extraction(
                 item_id=db_item.id,
                 image_bytes=image_bytes,