Transaction log stress tests

We need transaction log stress tests that generate hundreds of transaction log files in a short period of time to simulate an import. We need to better understand memory pressure around the memory maps and performance.

Specifically, can we release a memory map (https://github.com/HarperFast/rocksdb-js/issues/627) if the iterator is long-lived?

This stress test is going to be heavy. Just like benchmarks, only run the heavy stress tests when an environment variable flag is set.

We should probably set up a new CI workflow that is triggered by a cron schedule to run the full stress test suite nightly.