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Assistant API will be deprecated in 2026, replaced by Response API: https://platform.openai.com/docs/guides/responses-vs-chat-completions.

We should start support the Response API by introducing OpenAIAgent that is backed by the Response API, which can be stateful.

The new agent should conform to the behavior of AssistantAgent in AgentChat, while backed directly by the openai library.

Thoughts, feedback welcome!