Add Three.js web FactoryForge port

[auxon]

Summary

• Add a Vite + TypeScript + Three.js (WebGPU/WebGL) web client under web/ with ECS sim, HUD, save/load, AutoPlay, PvAI, and basic multiplayer scaffolding.
• Include keyboard/mouse controls with fixed WASD/arrow movement, building placement (clears trees in footprint), and transparent PNG sprite handling.
• Ship synced assets, shared data/protocol, and a lightweight WebSocket server for MP.

Test plan

• cd web && npm install && npm run dev - splash/menu ? New Game loads
• WASD and arrow keys move in the expected directions; facing animation matches
• Build (B) ? pick building ? LMB places; trees in footprint are cleared; status shows Place mode
• Transparent sprites (buildings/player/trees) have no colored underfill
• Optional: npm run server and Lobby connect path still opens without crashing