C1: delete generate/math_versor_arithmetic.py and its 3 tests (ADR-0139
add-only arithmetic spike; no runtime consumers, no pipeline wiring,
follow-on lift paused per module docstring).
C3: gitignore engine_state runtime artifacts (manifest.json,
recognizers.jsonl, discovery_candidates.jsonl). Module code
(engine_state/__init__.py) remains tracked; generated checkpoint
files should not be.
C5: document reader zero-delta root cause in train_sample/v1/README.md.
Both Phase 2 (whole-problem) and Phase 1 (question-only) reader paths are
called but inert because all 47 refusals are statement-level NO_INJECTOR
gaps, not question-sentence gaps. Reader unblocks when injector coverage
expands (C2 work). report.json use_reader flag corrected to reflect last run.
C6: add deprecation header to generate/math_parser.py pointing at
generate.math_candidate_graph.parse_and_solve as the live path.
C2/C4 briefs: docs/handoff/CLEANUP-C2-run-lane-migration.md and
docs/handoff/CLEANUP-C4-compositions-compile.md added as operator
dispatch docs for the medium-scope wiring tasks.