[code_review] Explore different values of temperature and top_p

[marco-c]

See Cheat Sheet: Mastering Temperature and Top_p in ChatGPT API
For example, make comment generation more creative, but keep filtering phase strict.

ea7cd01 was the first step for this.

This depends on #4580 for the evaluation.

[suhaibmujahid]

We have this as part of the experimental mode. We return the results generated by each of the models/configurations to the user for evaluation.

The following are the configurations in the experimental mode:

• gpt-4o temp 0.2
• gpt-4o temp 0.8
• claude-3-5 temp 0.2
• gemini-1.5-pro temp 0.2 (disabled due to a quota limitation error)