Fix supply chain delivery delays - implement immediate delivery

Removed all delivery delays from the supply chain:
- Set expected_delivery to 0 in generate_orders()
- Modified update_pending_orders() to deliver all orders immediately
- Removed delay logic from simulate_delivery_delays()

Bug fixes:
- Fixed missing assignment in update_pending_orders (line 135)
- Orders are now added to warehouse inventory immediately after generation

This resolves the issue where:
- Components were being ordered but never delivered
- Watches couldn't be assembled due to missing components
- Massive inventory buildup with expired components

The simulation now works correctly with immediate component delivery.