Show customers with overdue orders

[florinc]

Description

As a business user, I want to see all customers that have at least one overdue order, so that I can identify accounts that require follow up.

An order is considered overdue when its due date is earlier than today and its status is not closed.

Acceptance Criteria

• The feature lists only customers that have at least one overdue order.
• Orders are grouped by customer.
• Customers are ordered by the date of their oldest overdue order, ascending.
• For each customer, the following information is displayed:
  • Customer name
  • Number of overdue orders
  • Date of the oldest overdue order
• The feature is accessible through a console command.