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+- Added `OpenAIResponsesLLMService`, a new LLM service that uses the OpenAI Responses API. Supports streaming text, function calling, usage metrics, and out-of-band inference. Works with the universal `LLMContext` and `LLMContextAggregatorPair`. See `examples/foundational/07-interruptible-openai-responses.py` and `14-function-calling-openai-responses.py`.