Both not a likely problem with any recent model and absolutely mitigated by using it in a VM with snapshots, which, besides being good practice, is a technology that I expect selfhosters to be familiar with anyway.

If there are objections to major models, (economic, resource, moral, etc), this application is achievable with a self-hosted Qwen or similar, although it will take additional nudging. That’s harder to get started with, though, which is why I didn’t suggest it. Self-hosted Gemma 4 I would absolutely recommend using in a VM, it really likes to erase projects and start over, in my experience.

I hope that helps!