I made something pretty similar to this a couple months ago, when I was just getting into using coding agents. Has 2 parts that work individually but are better together: a change tracking FS and an agent sandbox. Haven't really used it though as it's a pain to get Claude Code working in that - Docker-based - sandbox without baking it in, and I really want something that's fully configurable. And then I didn't really need it to because I'm a very interactive user; I'm almost constantly watching the agent and never use YOLO... except for 1 codebase where it's frustratingly failing to fix a single particular bug and I really don't want to deal with it myself.