fix: use bare raise instead of raise e to preserve traceback

[hobostay]

Summary

• Fix improper exception re-raising in mcp_client.py:71 that loses the original traceback

Problem

In MCPClient.connect_and_discover(), the exception handler:

except Exception as e:
    raise e

This discards the original traceback, making it harder to debug issues. In Python, raise e creates a new exception from the current location, while bare raise preserves the original traceback and exception chain.

Fix

Changed to bare raise to preserve the full exception context for debugging.

Test plan

• Verify MCP connection errors still propagate correctly
• Verify traceback now shows the original error location

🤖 Generated with Claude Code

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