chore(routing): retire haiku from delivery-lifecycle roles (#680)

Haiku can't reliably emit the structured envelopes the lifecycle now
runs on — pass_review's per-AC criteria_verified, delegate's
covers_parent_criteria, the findings ledger. A haiku QA/PM claims, gets
validation-rejected, idles, respawns, and loops without advancing a task
(2026-07-24 live: fe-qa on haiku looped four awaiting_qa tasks to zero
progress). The per-token savings (~2x under the Sonnet-5 promo, 3x after)
are dwarfed by the cost of a review that never completes.

Three coordinated changes: ROLE_MODEL_MAP's qa/documenter defaults move
haiku -> sonnet (the actual source of the live incident); the cost_tiered
developer:low -> haiku seed retires to empty (the floor would upgrade it
anyway); and a structured-verb capability floor upgrades any below-floor
Anthropic assignment to sonnet at resolution — from a pin, a ROLE row,
or a future map edit — in both the assignment and legacy paths.
Non-Anthropic providers are untouched (an Anthropic-tier floor, not a
provider policy). pr_reviewer/auditor stay on opus.

Co-authored-by: Renn F <rennf93@users.noreply.github.com>

tests/unit/llm/test_routing_downgrade.py

@@ -77,3 +77,57 @@ async def test_resolve_for_agent_no_assignment_is_silent_legacy_fallback() -> No
 
     assert route.provider_type == ModelProvider.ANTHROPIC
     svc.log.warning.assert_not_called()
+
+
+@pytest.mark.asyncio
+async def test_haiku_lifecycle_assignment_upgraded_to_the_floor() -> None:
+    """The structured-verb capability floor: a haiku-class Anthropic
+    assignment on any lifecycle role resolves to sonnet instead, so a QA/PM
+    agent can produce the structured review envelopes (2026-07-24 retirement).
+    """
+    provider = MagicMock(
+        enabled=True, id="prov-anthropic", type=ModelProvider.ANTHROPIC
+    )
+    resolved = _ResolvedAssignment(
+        provider=provider,
+        model_name="claude-haiku-4-5-20251001",
+        scope=AssignmentScope.ROLE,
+    )
+    svc = _svc()
+    captured: dict[str, str] = {}
+
+    async def _fake_route(res: _ResolvedAssignment, _slug: str) -> object:
+        captured["model"] = res.model_name
+        return object()
+
+    with (
+        patch.object(svc, "_resolve_assignment", AsyncMock(return_value=resolved)),
+        patch.object(svc, "_route_from_resolved", _fake_route),
+    ):
+        await svc.resolve_for_agent("be-qa")
+
+    assert captured["model"] == "sonnet"
+
+
+@pytest.mark.asyncio
+async def test_non_anthropic_below_floor_name_is_untouched() -> None:
+    """The floor is an Anthropic-tier policy — a non-Anthropic model whose
+    name happens to contain the marker is never upgraded."""
+    provider = MagicMock(enabled=True, id="prov-grok", type=ModelProvider.GROK)
+    resolved = _ResolvedAssignment(
+        provider=provider, model_name="grok-haiku-ish", scope=AssignmentScope.ROLE
+    )
+    svc = _svc()
+    captured: dict[str, str] = {}
+
+    async def _fake_route(res: _ResolvedAssignment, _slug: str) -> object:
+        captured["model"] = res.model_name
+        return object()
+
+    with (
+        patch.object(svc, "_resolve_assignment", AsyncMock(return_value=resolved)),
+        patch.object(svc, "_route_from_resolved", _fake_route),
+    ):
+        await svc.resolve_for_agent("be-qa")
+
+    assert captured["model"] == "grok-haiku-ish"

tests/unit/models/test_model_map.py

@@ -23,9 +23,12 @@ def test_sonnet_5_is_priced() -> None:
     assert cost > 0.0
 
 
-def test_qa_role_routes_to_haiku() -> None:
-    # Phase 2: QA is mechanical gate work → cheapest tier.
-    assert ROLE_MODEL_MAP["qa"] == "haiku"
+def test_no_lifecycle_role_routes_below_the_structured_verb_floor() -> None:
+    # Retired haiku from lifecycle roles (2026-07-24): a haiku QA/documenter
+    # can't emit the structured review envelopes (criteria_verified, findings)
+    # and loops without passing. No role's default may be a haiku-class tier.
+    for role, model in ROLE_MODEL_MAP.items():
+        assert "haiku" not in model.lower(), f"{role} routes to a below-floor {model}"
 
 
 def test_main_pm_role_routes_to_sonnet() -> None: