[Fix] Support non-reasoning parameter for GPT-5 Chat model

[eycjur]

Support temperature for GPT-5 Chat model

GPT-5 chat is not an inference model, and since it requires support for parameters like temperature or tool_choice that are unavailable in inference models, I modified gpt_5_transformation to apply only when the model is a reasoning model.

Note: Since the current PR changes the public interface, if undesirable, it is also possible to retain the AzureOpenAIGPT5Config.is_model_gpt_5_model interface and set it to False for GPT-5 chat cases.

Relevant issues

Fixes #13781 and #14704

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Type

🐛 Bug Fix

Changes

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