- Add getCostBreakdown() for order cost calculation
- Add getOrderHistory() for change tracking
- Add assignTechnician() for mechanic assignment
- Add addDiscount() for order-level discounts
- Add updatePriority() for priority management
- Add searchOrders() with multi-field search
- Export new DTOs: ServiceContext, CostBreakdown, OrderHistoryEntry
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>