Clears the long-standing B4 block: the leeway decision was already made on the
serving path (chat/runtime.py::_surface_estimate has a real LicenseDecision +
the ReachPolicy) and then DISCARDED — never threaded to the result, and the
workbench can't import reliability_gate. This wires it through.
Producer (observational, never authorizing):
- core/cognition/leeway.py: LeewayRecord + build_leeway_record(reach_level,
license_decision) — duck-typed on the decision, zero new cross-package
coupling. Maps to: no decision -> "unknown" (STRICT, no latitude); denied
-> "blocked" (gate consulted, said no); licensed SERVE/PROPOSE widening ->
the real class / theta / "[approximate]" disclosure. "verified" is never
emitted (RESERVED state). source_digest content-addresses the decision
(deterministic, no wall-clock).
- core/cognition/result.py: additive `leeway: LeewayRecord | None = None` on
CognitiveTurnResult.
- core/cognition/pipeline.py: build it at result construction from the data
the runtime ALREADY exposes (response.reach_level +
runtime.last_turn_accrual().license). chat/runtime.py is UNTOUCHED.
- workbench/api.py: _leeway_evidence_from_result maps result.leeway ->
LeewayEvidence (pure projection; no reliability_gate import — firewall
intact). The journal already persists it; the B4a UI (Replay / Proposals /
RightInspector) already renders it — no frontend or schema change needed.
Safety (this touches the serving path, so proven, not asserted):
- trace_hash is a NAMED-field hash (core/cognition/trace.py); `leeway` is not
in it -> byte-identical serving. All provenance/trace tests pass.
- response_governance STRICT stays byte-identical (375 governance/serving/
provenance tests green, incl. the live-wiring + estimation-lane + ADR-0206
seam tests).
- core eval cognition: 13 cases, 100% intent / groundedness / versor closure.
- replay determinism holds (leeway is in CRITICAL_FIELDS; deterministic).
Tests: engine (build_leeway_record: strict/blocked/SERVE/PROPOSE, no "verified",
deterministic digest) + workbench mapping (field-for-field, honest absence,
invalid-enum clamp) + integration (a real turn now carries an honest leeway
record, not the null "No evidence recorded"). 151 workbench/leeway Python + 68
frontend (leeway/replay/proposals/schemaDrift) green; schema-snapshot unchanged.
Docs: gate cleared (b4-leeway-feasibility-gate.md), residue ledger flipped to
implemented, scope brief is b4-leeway-producer-scope-2026-06-13.md.
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