Finish KG-WP-0003: stream completeness and live qonto observation

Classify evidence as load-bearing or attributive, draft the emission-cadence
declaration for Taxonomy, treat silence as a stream finding, keep completeness
separate from record richness, forbid immune memory as a state plane, and make
containment proposals reconstructable to their origin. Observe real
qonto-assistant audit events; deny-class completeness stays unknown until the
source publishes a heartbeat.

Assistant: grok
Assistant-Session: 01a05ef1-9e5a-70f2-b0ff-0b05d6b38ae9

tests/test_completeness.py

@@ -0,0 +1,111 @@
+from kings_guard.cadence import load_qonto_assistant_cadence
+from kings_guard.contracts import (
+    PostureAssessment,
+    PostureLevel,
+    ReconciliationView,
+    StreamCompleteness,
+    StreamHeartbeat,
+    assessment_trust_key,
+)
+from kings_guard.posture import PostureEvaluator
+
+from helpers import load_pilot, observation_from_fixture
+
+
+def _healthy_assessment(*, completeness: StreamCompleteness, confidence: int) -> PostureAssessment:
+    return PostureAssessment(
+        posture=PostureLevel.HEALTHY,
+        risk_score=5,
+        confidence_score=confidence,
+        stream_completeness=completeness,
+        completeness_reason="test",
+        findings=(),
+        tolerated_findings=(),
+        rationale="test",
+    )
+
+
+def test_completeness_is_separated_from_record_richness() -> None:
+    fixture = load_pilot()
+    observation = observation_from_fixture(fixture)
+    evaluation = PostureEvaluator().evaluate(fixture.genome, observation)
+
+    assert evaluation.assessment.confidence_score >= 85
+    assert evaluation.assessment.stream_completeness is StreamCompleteness.UNKNOWN
+    assert "record" in evaluation.assessment.completeness_reason
+    assert "cannot vouch" in evaluation.assessment.rationale or "unknown" in evaluation.assessment.rationale
+
+
+def test_unmet_cadence_degrades_completeness_and_says_so_in_words() -> None:
+    fixture = load_pilot()
+    observation = observation_from_fixture(fixture)
+    cadence = load_qonto_assistant_cadence()
+    evaluation = PostureEvaluator().evaluate_with_stream(
+        fixture.genome,
+        observation,
+        cadence,
+        now="2026-07-24T10:10:00Z",
+        watching_since="2026-07-22T09:10:00Z",
+        heartbeats=(),
+        reconciliation=ReconciliationView(source_counts={"audit.deny": 1}, evidence_counts={"audit.deny": 1}),
+    )
+
+    assert evaluation.assessment.stream_completeness is StreamCompleteness.DEGRADED
+    assert evaluation.assessment.confidence_score >= 85
+    assert "cannot vouch" in evaluation.assessment.rationale
+
+
+def test_incomplete_stream_is_never_more_trustworthy_than_a_complete_one() -> None:
+    rich_incomplete = _healthy_assessment(
+        completeness=StreamCompleteness.DEGRADED, confidence=95
+    )
+    sparse_complete = _healthy_assessment(
+        completeness=StreamCompleteness.COMPLETE, confidence=70
+    )
+    unknown = _healthy_assessment(completeness=StreamCompleteness.UNKNOWN, confidence=95)
+
+    assert assessment_trust_key(rich_incomplete) < assessment_trust_key(sparse_complete)
+    assert assessment_trust_key(unknown) < assessment_trust_key(sparse_complete)
+    assert assessment_trust_key(unknown) < assessment_trust_key(rich_incomplete)
+
+
+def test_complete_stream_keeps_richness_and_states_completeness() -> None:
+    fixture = load_pilot()
+    observation = observation_from_fixture(fixture)
+    cadence = load_qonto_assistant_cadence()
+    allow_event = dict(fixture.audit_event)
+    allow_event["decision"] = "allow"
+    allow_event["deny_reason"] = None
+    allow_event["request_id"] = "req-allow-volume"
+    from kings_guard.adapters import observation_from_audit_event
+
+    allow = observation_from_audit_event(
+        allow_event,
+        subject_id=fixture.normalization_hints["subject_id"],
+        capability_scope=fixture.normalization_hints["capability_scope"],
+        identity_binding=fixture.normalization_hints["identity_binding"],
+        egress_destination=fixture.normalization_hints["egress_destination"],
+        genome=fixture.genome,
+    )
+    evaluation = PostureEvaluator().evaluate_with_stream(
+        fixture.genome,
+        observation,
+        cadence,
+        now="2026-07-24T09:10:00Z",
+        observations=(observation, allow),
+        watching_since="2026-07-22T09:10:00Z",
+        heartbeats=(
+            StreamHeartbeat(
+                source_system="qonto-assistant",
+                timestamp="2026-07-24T09:00:00Z",
+                event_class="audit.heartbeat",
+                assertion="nothing-to-report",
+                counts={"audit.deny": 1},
+            ),
+        ),
+        reconciliation=ReconciliationView(source_counts={"audit.deny": 1}, evidence_counts={"audit.deny": 1}),
+    )
+
+    assert evaluation.assessment.stream_completeness is StreamCompleteness.COMPLETE
+    assert "Stream completeness is complete." in evaluation.assessment.rationale
+    assert evaluation.assessment.confidence_score >= 85