Scaffolding log (human/assistant written, before and between swarm runs).
Every change to a non-src/ path is listed here with its reason.

- scaffold: grader (slt/), generated tests, score example, SQLite oracle,
  tier-1 corpus (select1-5, evidence/), proof files. Oracle 11,183/11,185.
- experiment: head-to-head design (PROOF.md), shared goal (scaffold/goal.txt),
  solo-arm runner (scaffold/arm_solo.py). No change to the grader, tests or corpus.
- fix: solo runner launches claude.exe directly (the PATH entry is a .cmd wrapper); found in a 90 s dry run on a throwaway clone.
- aborted launch 01:57: a test launch of Arm B from a terminal ran ~20 s and was killed by a timeout; its round-1 commit (1 -> 181) is kept on branch aborted-launch-0157. It exposed two throng issues, fixed before the real Arm B: Claude Code workers could outlive a killed throng (now tied to a job object that dies with throng; verified), and failure groups keyed on query text (457 groups of ~2) instead of the failure reason (fixed, with a test).