I’ve been wanting the same thing. I am currently experimenting with a container that adds what I want. I keep wanting my sandboxed dev machine that is preconfigured with Claude (and almost nothing else)…but then I also want my customized Claude. I saw someone here on HN the other day who just spins up a Docker container and shares their home directory Claude files with it to facilitate the customized Claude container:

https://news.ycombinator.com/item?id=44549802

You can do this with devcontainer and still work within VSCode.