- storage/schema.py: `runs` table recording every evaluated configuration,
feasible or not, with an honest infeasible_reason instead of dropping
failures
- storage/database.py: WAL-mode SQLite, single-writer-over-a-queue pattern
for safe concurrent writes from many sweep worker processes
- Testing with real multiprocessing.Process (not mocks) caught a genuine
bug: a duplicate run_id raised inside the writer loop and killed the
writer process, silently halting queue drainage for the rest of a
sweep. Fixed by catching the insert error per-record and logging to
stderr instead of crashing; added a regression test for it.
- Verified locally and inside the Docker image (43/43 tests both ways)
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
