Add Multiplayer (PartyKit / Cloudflare Durable Objects) Add real-time or turn-based multiplayer to an existing single-player browser game. This skill scaffolds: 1. A PartyKit server (one Durable Object per room) deployed to Cloudflare's edge. 2. A client wired through EventBus that mirrors the existing external-service pattern. 3. Additive edits to , , , and — single-player gameplay must remain identical when the server is unreachable. The default state is "single-player works." If the WebSocket connection fails, NetworkManager swallows the error and the game runs locally as before. When conn…