fix: add ensure_ascii=False to json.dumps for correct Unicode output

Author: KatHaruto

src/agents/models/openai_responses.py

@@ -231,8 +231,8 @@ async def _fetch_response(
         else:
             logger.debug(
                 f"Calling LLM {self.model} with input:\n"
-                f"{json.dumps(list_input, indent=2)}\n"
-                f"Tools:\n{json.dumps(converted_tools.tools, indent=2)}\n"
+                f"{json.dumps(list_input, indent=2, ensure_ascii=False)}\n"
+                f"Tools:\n{json.dumps(converted_tools.tools, indent=2, ensure_ascii=False)}\n"
                 f"Stream: {stream}\n"
                 f"Tool choice: {tool_choice}\n"
                 f"Response format: {response_format}\n"