Simplified the trade machine by removing the redundant InFlight state. Flight handling is now fully delegated to travelToLocationMachine, reducing duplication and complexity.

Fixed several edge cases in the trading flow: handling ships that are mid-way through a route when the app restarts, proper trade completion detection, and fuel calculation accuracy. Ships now update their fuel state when creating flight plans.

Improved performance by keeping locations in memory instead of constantly reading from localStorage. Added a sleep utility for controlled delays.

Enhanced debugging with the ability to toggle debug mode without restarting the app. Improved error logging throughout the ship machines.