Session Break Summary - 2026-07-19 13:10

Current State

Branch: feat/reader-inc2-caseband (pushed to remote, maps to PR #80)
Worktree: core-wt-inc2
What was just completed:
- Fixed _token_in in generate/math_roundtrip.py to enforce contiguous substrings when matching multi-word phrases, addressing a latent wrong=0 hole.
- Successfully ran smoke validation suite and holdout_dev/v1 exact measurement.
- Case 0148 is confirmed solved, converting 1 case while holding wrong=0 perfectly across the full 500 cases (correct=6 wrong=0 refused=494 (n=500)).
- Graph dump for case 0148 committed to docs/research/0148-first-conversion-proof.md as proof of correct-for-the-right-reason binding.
- PR #80 is updated with these fixes and ready for merge.

Merge PR #80 to ratify Increment 2 (CASE-FIRST) and officially claim the first conversion of this arc.
Review/Execute next targets:
- 0001 (fast-follow): Needs than alongside as + aggregate "two other harbors combined" + "each".
- q:complex decomposition direction.

The solver is currently fail-closed and strictly guards wrong=0. When introducing the 0001 capabilities (e.g. two other harbors combined as a 2-peer sum), ensure that aggregate logic remains defensively bounded and doesn't pollute the broader wrong=0 baseline.

docs/research/increment-2-caseband-plan-2026-07-19.md (for the planned continuation work on 0001)
generate/math_roundtrip.py (specifically _token_in)
generate/math_candidate_parser.py