shepherd｜支持95% KV缓存复用的智能体执行追踪shepherd-agents/shepherd

shepherd：运行时基底，将智能体执行转为可逆的Git风格追踪，支持元智能体观察、分叉、回放和回滚，KV缓存复用率达95%，性能优于Docker提交。 A runtime substrate that turns an agent's execution into a reversible, Git-like trace, so meta-agents can observe, fork, replay, and revert any run. Couples agent and environments in a copy-on-write fork ~5x faster than docker commit, with ~95% KV-cache reuse on replay. Framework built for meta-agents to supervise, optimize, and train other agents