trading-mcp

## ADDED Requirements ### Requirement: Standard market data interface The system SHALL define a market data client interface that provides a method to fetch time-series data by symbol and date range. #### Scenario: Fetch returns time-series data - **WHEN** the client is called with a symbol and date range - **THEN** it returns a time-ordered dataset for that symbol and range ### Requirement: Akshare implementation is provided The system SHALL provide an Akshare-based implementation of the market data client interface. #### Scenario: Akshare client fulfills interface - **WHEN** the Akshare client is used to fetch data - **THEN** it returns data in the same structure defined by the interface