Implement concurrent order-accept/pickup simulator

## Concurrent restaurant order + pickup simulator Design and implement a **thread-safe** simulation for a restaurant that: - Receives incoming orders concurrently (multiple producer threads). - Prepares orders concurrently (one or more worker/chef threads). - Allows customers to pick up orders concurrently (multiple consumer threads). ### Requirements 1. Each order has: - `order_id` (unique integer) - `item_name` (string) - `cook_time_ms` (positive integer) 2. API / operations to support (names can vary): - `placeOrder(order_id, item_name, cook_time_ms)` - `startKitchen(num_chefs)` (starts background processing) - `pickupOrder(order_id)` blocks until the specified order is ready, then returns it - `shutdown()` stops background threads gracefully 3. Correctness constraints: - No order can be picked up before it is cooked. - Each order is cooked **exactly once** and picked up **at most once**. - No deadlocks; avoid busy-waiting. - The system should handle `N` orders with concurrent placement and pickup. ### What to discuss/implement - Your choice of synchronization primitives (mutex/lock, condition variable, semaphore, blocking queue, etc.). - Data structures used to track order state. - How you ensure fairness and avoid race conditions. (You may assume a single process and shared memory; no networking required.)