Design crypto trading order control API

You are implementing part of a simple crypto trading system that manages client orders. Each order can be in one of several states: NEW, ACTIVE, PAUSED, CANCELLED, or FILLED.

You need to support the following operations for a single order (you can assume order creation is already done):

1. pause(orderId) : Temporarily pause an active order so that it will not be matched or executed while paused.
2. resume(orderId) : Resume a paused order so that it becomes active again and can be matched.
3. cancel(orderId) : Cancel an order so that it will never be executed in the future.

Rules and constraints:

• Valid state transitions are:
  • NEW -> ACTIVE
  • ACTIVE -> PAUSED
  • PAUSED -> ACTIVE (on resume)
  • ACTIVE -> CANCELLED
  • PAUSED -> CANCELLED
  • ACTIVE -> FILLED
• Once an order is in CANCELLED or FILLED , no further operations ( pause , resume , or cancel ) should change its state.
• pause on a non- ACTIVE order should be rejected.
• resume on a non- PAUSED order should be rejected.
• cancel on a CANCELLED or FILLED order should be a no-op or return an error (choose one behavior and be consistent).

Implement a small in-memory component that:

• Stores the current state of each order by orderId .
• Exposes methods pause , resume , and cancel that update state according to the rules above.
• Returns success/failure for each operation based on whether the transition is allowed.

Describe your data structures and implement the core logic for these operations.