Please add prompt caching to Jev-style models

If you're building a Jev-style "System One" model, please add prompt caching or reusable question sets to your API 🙏. This would make batch use cases even more efficient, so you could amortize the cost of many questions asked over the same input. (This was also proposed in typesafe-ai/typesafe-sdk-js#10.) TL;DR: after a week of tweaking my Jev calls, my questions are ~88% of the input tokens. I'm asking 54 questions of ~1.1 million documents per month. Jev makes certain types of classification tasks easy and cheap, but prompt caching would make batch workflows even more cost effective. For me, the total dollar amount is still reasonable (less than $150 per month), but I'm sure others will hammer these APIs even harder. ContextI work on Scour. It’s a personalized content feed where you describe topics you’re interested in and it finds articles and blog posts related to them. For some time, I’ve wanted to ask slightly fuzzy questions of each piece of content Scour pulls in. What level…