Simplify order creation and editing - remove autosave

- Removed autosave.js (665 lines) and draft-creator.js (441 lines)
- Removed draft_service.py (~500 lines) and DraftOrderService
- Removed AJAX endpoints: autosave and create-draft
- Updated order_create() to add is_create_page flag
- Updated order_update() to finalize drafts without DraftOrderService
- Added get_new_status() method to OrderStatusService
- Updated order_form.html:
  - Removed old JS includes
  - Added beforeunload warning for unsaved data
  - Updated buttons: separate buttons for create/draft/finalize
- Total code reduction: ~1600 lines (92% removed)

New workflow:
- /orders/create/ - user fills form, chooses button
- /orders/<id>/edit/ - simple editing without autosave
- beforeunload warning when leaving page (except on submit)

myproject/orders/urls.py

@@ -12,8 +12,6 @@ urlpatterns = [
     path('<int:order_number>/delete/', views.order_delete, name='order-delete'),
 
     # AJAX endpoints
-    path('<int:order_number>/autosave/', views.autosave_draft_order, name='order-autosave'),
-    path('create-draft/', views.create_draft_from_form, name='order-create-draft'),
     path('api/customer-address-history/', views.get_customer_address_history, name='api-customer-address-history'),
 
     # Wallet payment