fix(voice): fast fallback for off-domain requests

tests/test_ai_orchestrator_service.py

@@ -1356,6 +1356,46 @@ def test_voice_v2_fast_conversational_adds_ack_metadata_and_compacts_reply(monke
     assert len(decision["reply_text"]) <= 180
 
 
+def test_voice_v2_off_domain_request_returns_fast_operator_fallback_without_llm(monkeypatch):
+    monkeypatch.setenv("AI_VOICE_POLICY_MODE", "v2_fast_conversational")
+
+    def _unexpected_llm(messages):
+        raise AssertionError(f"LLM should not be called for off-domain fallback: {messages!r}")
+
+    monkeypatch.setattr(ai_module, "_request_structured_model_decision", _unexpected_llm)
+
+    decision = voice_module._voice_decision(
+        language="ru",
+        customer=None,
+        interaction=SimpleNamespace(interaction_id="int_voice_off_domain", status="new", queue_id="que_voice", subject="unknown"),
+        transcript_text="Мне надо узнать, как работает ядерный реактор.",
+        transcript_window=[
+            SimpleNamespace(
+                speaker="caller",
+                text="Мне надо узнать, как работает ядерный реактор.",
+                sequence_no=1,
+                source_type="voice_asr",
+                barge_in_interrupted=False,
+                created_at=utc_now_iso(),
+            )
+        ],
+        kb_results=[],
+        disclosure_required=False,
+        request_metadata={"voice_v2_enabled": True, "response_plan_id": "rsp_off_domain"},
+    )
+
+    assert decision["intent"] == "clarification"
+    assert decision["needs_handoff"] is False
+    assert decision["model"] == "voice_policy_off_domain"
+    assert "наших услуг" in decision["reply_text"].lower()
+    assert "оператор" in decision["reply_text"].lower()
+    assert "ai" not in decision["reply_text"].lower()
+    assert "база знаний" not in decision["reply_text"].lower()
+    assert decision["metadata"]["voice_v2_enabled"] is True
+    assert decision["metadata"]["early_intent"] == "unknown"
+    assert decision["metadata"]["response_plan_id"] == "rsp_off_domain"
+
+
 def test_ai_enqueue_creates_outbound_ai_reply_and_delivery_flow(monkeypatch):
     monkeypatch.setenv("AI_TELEGRAM_ENABLED", "1")
     monkeypatch.setenv("AI_PROVIDER", "stub")