ADR-0174 Phase 1 — substrate only, no admission behavior change.
Adds to generate/comprehension/state.py:
- HYPOTHESIS_CAP (=4, structural assertion per ADR-0174 §Constraints)
- VALID_HYPOTHESIS_CONFIDENCE_RANKS (closed set, no probabilistic ranking)
- Hypothesis dataclass (frozen, slots) — candidate, category_assignments,
constraint_state, confidence_rank, unresolved. The 'candidate' field is
typed as object to avoid circular import on math_roundtrip /
math_candidate_graph candidate types; Phase 2 will pin canonical_bytes
contract over real candidates.
- UnknownHeld dataclass — token, position, narrowed_categories (frozenset).
Substrate for Phase 3 'hold instead of refuse' on unknown words; Phase 1
introduces only the type.
- ProblemReadingState.open_hypotheses + unknown_held fields, both default
to () (empty tuple). Defaults preserve today's single-committed behavior
exactly. Confidence-rank uniqueness + density-from-0 enforced at
__post_init__ as structural invariants.
- Canonical-bytes serializer extended to handle frozenset (sorted list).
Phase 1 acceptance verified:
- 29/29 ADR-0174 Phase 1 tests pass (construction, validation, cap
enforcement, canonical-bytes determinism, frozenset stability).
- 42/42 existing reader tests pass (test_brief_11_audit +
test_reader_phase2) — default-empty fields preserve byte-identity.
- Smoke 67/67, packs 141/141.
- train_sample/v1 byte-identical across two runs with use_reader=True.
- wrong=0 invariant held: 3/47/0 unchanged.
No apply_word body changes. The 'thread the hypothesis set' requirement
at Phase 1 is satisfied by field defaults that propagate through every
ProblemReadingState construction site in lifecycle.py without code edits.
Phase 2 (continuous constraint propagation) and Phase 3 (lookback
re-evaluation) will populate these fields with real hypothesis data and
wire the EMIT / ELIMINATE / HOLD operators.
a713d2db33