Implement flexible order status management system

Features:
- Created OrderStatus model for managing statuses per tenant
- Added system-level statuses: draft, new, confirmed, in_assembly, in_delivery, completed, return, cancelled
- Implemented CRUD views for managing order statuses
- Created OrderStatusService with status transitions and business logic hooks
- Updated Order model to use ForeignKey to OrderStatus
- Added is_returned flag for tracking returned orders
- Updated filters to work with new OrderStatus model
- Created management command for status initialization
- Added HTML templates for status list, form, and confirmation
- Fixed views.py to use OrderStatus instead of removed STATUS_CHOICES

🤖 Generated with Claude Code

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

myproject/inventory/migrations/0002_initial.py

@@ -1,4 +1,4 @@
-# Generated by Django 5.0.10 on 2025-11-09 22:18
+# Generated by Django 5.0.10 on 2025-11-13 13:12
 
 import django.db.models.deletion
 from django.db import migrations, models