Add an indicator in the results directory that an evaluation has completed

[zimmski]

Please help us keep the number of duplicated issues small. We kindly ask you to add your input to the appropriate issue or PR in case your feature idea is already being tracked.

• [x] I have searched the existing feature requests, latest roadmap and open pull requests.

Problem

I am currently going through failed LLM CI jobs, and remove half-baked data. That is cumbersome to the extreme. And,

Solution (optional)

Add some form of indicator that a run has been completed. This would be also a nice step towards resuming a run.