Implement a fully playable Ticket to Ride game featuring a pure logic engine,
heuristic AI opponent, and Phaser UI scene.
Key additions:
- Board geometry, route definitions, destination tickets, and train card data
- State management, turn flow, payment validation, and scoring (routes, tickets, longest path bonus)
- AI decision-making for claiming routes, drawing cards/tickets, and endgame strategy
- Frontend integration (scene registration, opponent count default, slug dispatch)
- Server game registry configuration (supports 2-5 players)
Follows the existing architecture separating data, logic, AI, and rendering.