refactor: подготовка к стандартизации Transfer моделей

Текущее состояние перед рефакторингом Transfer → TransferDocument.
Все изменения с последнего коммита по улучшению системы поступлений.

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Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

myproject/inventory/forms.py

@@ -4,7 +4,7 @@ from django.core.exceptions import ValidationError
 from decimal import Decimal
 
 from .models import (
-    Warehouse, Incoming, Sale, WriteOff, Transfer, Reservation, Inventory, InventoryLine, StockBatch,
+    Warehouse, Sale, WriteOff, Transfer, Reservation, Inventory, InventoryLine, StockBatch,
     TransferBatch, TransferItem, Showcase, WriteOffDocument, WriteOffDocumentItem, Stock,
     IncomingDocument, IncomingDocumentItem, Transformation, TransformationInput, TransformationOutput
 )