feat: Airwallex 发卡管理后台完整实现

- 后端: FastAPI + SQLAlchemy + SQLite, JWT认证, 代理支持的AirwallexClient
- 前端: React 18 + Vite + Ant Design 5, 中文界面
- 功能: 卡片管理, 持卡人管理, 交易记录, API令牌, 系统设置, 审计日志
- 第三方API: X-API-Key认证, 权限控制
- Docker部署: docker-compose编排前后端

backend/app/config.py

@@ -0,0 +1,38 @@
+"""Application configuration using pydantic-settings."""
+import secrets
+from typing import Optional
+
+from pydantic_settings import BaseSettings, SettingsConfigDict
+
+
+class Settings(BaseSettings):
+    """Application settings loaded from environment variables and .env file."""
+
+    model_config = SettingsConfigDict(
+        env_file=".env",
+        env_file_encoding="utf-8",
+        case_sensitive=False,
+    )
+
+    # Admin credentials
+    ADMIN_USERNAME: str = "admin"
+    ADMIN_PASSWORD: str = "admin123"
+
+    # JWT settings
+    SECRET_KEY: str = secrets.token_urlsafe(32)
+    JWT_ALGORITHM: str = "HS256"
+    JWT_EXPIRE_MINUTES: int = 480
+
+    # Database
+    DATABASE_URL: str = "sqlite:///./data/airwallex.db"
+
+    # Airwallex API
+    AIRWALLEX_CLIENT_ID: str = ""
+    AIRWALLEX_API_KEY: str = ""
+    AIRWALLEX_BASE_URL: str = "https://api.airwallex.com/"
+
+    # Proxy (optional)
+    PROXY_URL: Optional[str] = None
+
+
+settings = Settings()