First phase of the domain-general compositional reading layer (the comprehension
coverage wall is composition — docs/analysis/comprehension-coverage-wall-map-2026-06-14.md).
M1 is a pure PARITY refactor on the flagship logic path, no new capability:
- new generate/composition/ package: LogicChainPlan (plan.py) + lower_logic_chain
(lower_logic.py), the is-a chain lowering extracted BYTE-IDENTICALLY from
determine.py::_verify_subsumption.
- _verify_subsumption now builds a plan -> lowers it -> routes through the UNCHANGED
evaluate_entailment gate. The composer proposes structure; the sound ROBDD gate
remains the sole wrong=0 firewall.
- only the logic instantiation ships; no math lowering, no join-op vocabulary
(defer-substrate-vocab-commitment — the chain discriminates on its relational
predicate, an explicit join-op field lands when a second op dispatches on it).
Verification: byte-identical lowering (3-reviewer adversarial panel: byte-parity PASS
char-for-char, wrong=0 PASS — the instance-of-fallacy refusal mutation-proven
load-bearing); 5 new non-vacuous lowering tests; 28 determine/transitive/consolidation
+ 163-test broad sweep (incl. gsm8k serving + ADR-0218) green; cognition eval 100%.
