Real-Time Options Chain Data Aggregation API Pipeline

Design a Python microservice using Flask that creates a robust API endpoint for aggregating real-time options chain data from multiple financial data providers. Implement rate limiting, authentication via JWT, and include comprehensive error handling for scenarios like provider API failures. The solution must support concurrent data fetching, normalize response formats across different providers, and include a caching mechanism to reduce external API calls. Provide a complete implementation with type hints, async capabilities, and a sample Swagger/OpenAPI documentation.