fix: update integration test, remove unused import, fix stale comment

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

tests/test_integration.py

@@ -123,13 +123,12 @@ def test_full_pipeline(table_client, tmp_path):
     scan_rows = list(read_csv(scan_path))
     assert len(scan_rows) == len(orders)  # all orders, no filtering
 
-    # --- Backup (Jan 1-2 only) ---
+    # --- Backup (before Jan 3) ---
     backup_dir = tmp_path / "backups"
     count = backup_orders(
         scan_path=scan_path,
         backup_dir=backup_dir,
-        start=datetime(2025, 1, 1, tzinfo=timezone.utc),
-        end=datetime(2025, 1, 3, tzinfo=timezone.utc),
+        cutoff=datetime(2025, 1, 3, tzinfo=timezone.utc),
     )
     # 2 days × 2 users × 2 Recived = 8 orders
     assert count == 8