feat: implement hybrid database architecture and frontend encryption

- Add PostgreSQL + SQLite hybrid database support with automatic switching
- Implement frontend AES-GCM + RSA-OAEP encryption for sensitive data
- Add comprehensive DatabaseInterface with all required methods
- Fix compilation issues with interface consistency
- Update all database method signatures to use DatabaseInterface
- Add missing UpdateTraderInitialBalance method to PostgreSQL implementation
- Integrate RSA public key distribution via /api/config endpoint
- Add frontend crypto service with proper error handling
- Support graceful degradation between encrypted and plaintext transmission
- Add directory creation for RSA keys and PEM parsing fixes
- Test both SQLite and PostgreSQL modes successfully

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: tinkle-community <tinklefund@gmail.com>

docker-compose.yml

@@ -56,6 +56,7 @@ services:
       - /etc/localtime:/etc/localtime:ro  # Sync host time
     environment:
       - TZ=${NOFX_TIMEZONE:-Asia/Shanghai}  # Set timezone
+      - AI_MAX_TOKENS=4000  # AI响应的最大token数（默认2000，建议4000-8000）
       - POSTGRES_HOST=postgres
       - POSTGRES_PORT=5432
       - POSTGRES_DB=${POSTGRES_DB:-nofx}