feat: Initial project structure for WebTriviasMulti

- Backend: FastAPI + Python-SocketIO + SQLAlchemy
  - Models for categories, questions, game sessions, events
  - AI services for answer validation and question generation (Claude)
  - Room management with Redis
  - Game logic with stealing mechanics
  - Admin API for question management

- Frontend: React + Vite + TypeScript + Tailwind
  - 5 visual themes (DRRR, Retro, Minimal, RGB, Anime 90s)
  - Real-time game with Socket.IO
  - Achievement system
  - Replay functionality
  - Sound effects per theme

- Docker Compose for deployment
- Design documentation

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/app/config.py

@@ -0,0 +1,47 @@
+from pydantic_settings import BaseSettings
+from functools import lru_cache
+
+
+class Settings(BaseSettings):
+    # Database
+    database_url: str = "postgresql://trivia:trivia@localhost:5432/trivia"
+
+    # Redis
+    redis_url: str = "redis://localhost:6379"
+
+    # JWT
+    jwt_secret: str = "dev-secret-key-change-in-production"
+    jwt_algorithm: str = "HS256"
+    jwt_expire_minutes: int = 1440  # 24 hours
+
+    # Anthropic
+    anthropic_api_key: str = ""
+
+    # Game settings
+    default_times: dict = {
+        1: 15,  # 100 pts
+        2: 20,  # 200 pts
+        3: 25,  # 300 pts
+        4: 35,  # 400 pts
+        5: 45,  # 500 pts
+    }
+
+    default_points: dict = {
+        1: 100,
+        2: 200,
+        3: 300,
+        4: 400,
+        5: 500,
+    }
+
+    steal_penalty_multiplier: float = 0.5
+    steal_time_multiplier: float = 0.5
+
+    class Config:
+        env_file = ".env"
+        extra = "ignore"
+
+
+@lru_cache()
+def get_settings() -> Settings:
+    return Settings()