Unless you are doing something crazy like letting the fuzzer run on every change (cache that shit), the full test suite taking a long time suggests that either your isolation points are way too large or you are letting the LLM cross isolated boundaries and "full testing suite" here actually means "multiple full testing suites". The latter is an easy fix: Don't let it. Force it stay within a single isolation zone just like you'd expect of a human. The former is a lot harder to fix, but I suppose ending up there is a strong indicator that you can't trust the human picking the best LLM result in the first place and that maybe this whole thing isn't a good idea for the people in your organization.