Add 3 A-share quant projects (mcp-eastmoney, mx-backtest, mx-risk-guard)

[27dream]

Added

• mcp-eastmoney → Market Data: MCP server for real-time A-share data via East Money, no API key required
• mx-backtest → Trading & Backtesting: Event-driven backtesting engine for A-shares (T+1, price limits, etc.)
• mx-risk-guard → Portfolio Risk: Broker-agnostic A-share trading risk control engine

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All projects are MIT-licensed and actively maintained.

Note: mx-trader-bridge was already present in this list — keeping it, just adding 3 more.

[wilsonfreitas]

Thanks for the contribution. Please clean and rebase this branch so it contains only the three intended additions: mcp-eastmoney, mx-backtest, and mx-risk-guard. The current diff changes many unrelated existing entries and re-adds mx-trader-bridge, which is already present in the README. After cleanup, please run the README validator and ensure each retained entry is unique and follows the current tag and description format.