[Tankenstein]

This is the first time since GPT 4.1 that I think I can upgrade our main agent model. Any noticeable amount of reasoning has been too slow for us, since the model is having a real-time conversation with the user. "minimal" reasoning GPT-5 performs terribly, it's significantly dumber than GPT 4.1 in a long, multi-turn conversation with tools.

This time, I just dropped it in and at first glance it seems to work well. I'll probably upgrade over the weekend if I see a boost in performance somewhere after tuning the prompts.