Cache airline flight DB and harden adapters

[benjibc]

Summary

• cache the tau2 airline FlightDB and reuse copies across environment resets to avoid disk reloads during server startup
• harden the Langfuse and LangSmith adapters to tolerate missing optional dependencies while keeping proper client typing
• extend the MCP session autocreation test with an explicit readiness timer assertion to guard server boot duration

Testing

• pre-commit run --all-files
• pytest tests/pytest/test_mcp_session_autocreate.py

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https://chatgpt.com/codex/tasks/task_e_68cc8a9847dc833383caa7a352423074