* fix(llm): omit temperature for OpenAI GPT-6 family (#1101)
Official openai channel already skipped temperature for gpt-5* (#857);
GPT-6 Astra/Sol/Luna reject non-default temperature the same way. Extend
the omit rule and cover display-name / prefixed model ids in unit tests.
* test(llm): tighten GPT-6 API model coverage
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Co-authored-by: Chris233 <h-chris233@outlook.com>