세션 평가·라이브코치·교수자 분석 라운드 마감 + 문서 정리 + 코드품질 리팩터

- 누적 작업트리 커밋: 회기 평가 복구·durable 저장, 라이브 코치 이력/근거, 교수자 학생분석, 음성 비언어 메타, PII 마스킹, 운영 티켓/헬스 등
- 문서: 완료 기록 docs/archive/ 냉동 보관, docs/ 단일 인덱스(docs/README.md)+통합 TODO(docs/TODO.md)로 정리
- 리팩터(행위 보존): Stage enum SSOT(taxonomy 소유·state_machine re-export), store recent/masked_turns 중복 제거, speaker_ko_label 단일 헬퍼, _list_sessions N+1 제거(state/turns 배치 + 턴평가 하이드레이션 배치)
- 검증: 백엔드 pytest 352 passed, _list_sessions E2E chromium-single-run 2 passed

apps/api/app/test_voice_ws.py

@@ -7,6 +7,8 @@ import unittest
 from types import SimpleNamespace
 from unittest.mock import AsyncMock, patch
 
+from fastapi import HTTPException
+
 from .deps import Principal, Role
 from .persona_repository import PersonaVoiceMap
 from .routes import voice as voice_routes
@@ -17,13 +19,20 @@ SESSION_ID = "voice-ws-contract-session"
 VOICE_PRESET = VoicePreset(preset="neutral", openai_voice="sage")
 
 
-def _principal(role: Role = Role.LEARNER) -> Principal:
+def _principal(
+    role: Role = Role.LEARNER,
+    *,
+    consent_at: float | None = 1.0,
+    profile_completed_at: float | None = 1.0,
+) -> Principal:
     return Principal(
         user_id="00000000-0000-0000-0000-000000000201",
         role=role,
         cohort_ids=[],
         email=f"voice-ws-{role.value}@hs.ac.kr",
         display_name="Voice WS Contract",
+        consent_at=consent_at if role == Role.LEARNER else None,
+        profile_completed_at=profile_completed_at if role == Role.LEARNER else None,
     )
 
 
@@ -318,6 +327,55 @@ class VoiceWebSocketContractTest(unittest.IsolatedAsyncioTestCase):
         self.assertEqual(kwargs["voice_preset"], VOICE_PRESET)
         self.assertEqual(kwargs["learner_text"], "I need help practicing.")
 
+    async def test_turn_persistence_failure_uses_structured_voice_error(self) -> None:
+        websocket = FakeWebSocket(
+            [
+                _control({"type": "text_turn", "text": "I need help practicing."}),
+                _control({"type": "close"}),
+            ]
+        )
+        run_turn = AsyncMock(
+            side_effect=HTTPException(
+                status_code=503,
+                detail=(
+                    "voice session turn append persistence unavailable; "
+                    "runtime fallback is disabled in prod"
+                ),
+            )
+        )
+
+        with patch.object(
+            voice_routes,
+            "_principal_from_websocket",
+            AsyncMock(return_value=_principal()),
+        ), patch.object(
+            voice_routes,
+            "_bind_session",
+            AsyncMock(return_value=self._bind_result()),
+        ), patch.object(
+            voice_routes.voice_service,
+            "is_available",
+            return_value=True,
+        ), patch.object(
+            voice_routes,
+            "_run_turn_and_speak",
+            run_turn,
+        ):
+            await voice_routes.voice_ws(websocket)  # type: ignore[arg-type]
+
+        self.assertEqual(websocket.close_codes, [1000])
+        self.assertEqual(websocket.sent_json[0].get("type"), "ready")
+        self.assertEqual(websocket.sent_json[0].get("state"), "idle")
+        self.assertEqual(
+            websocket.sent_json[-2],
+            {
+                "type": "error",
+                "code": "turn_persistence_unavailable",
+                "detail": "voice turn persistence unavailable; retry the utterance",
+            },
+        )
+        self.assertEqual(websocket.sent_json[-1], {"type": "state", "state": "idle"})
+
     async def test_stt_result_waits_for_final_transcript_before_running_turn(self) -> None:
         websocket = FakeWebSocket(
             [
@@ -606,6 +664,60 @@ class VoiceWebSocketContractTest(unittest.IsolatedAsyncioTestCase):
         ))
         get_voice_map.assert_awaited_once_with(SESSION_ID)
 
+    async def test_bind_session_rejects_existing_session_without_onboarding(self) -> None:
+        websocket = FakeWebSocket()
+        websocket.query_params = {"session_id": SESSION_ID}
+        load_voice_session = AsyncMock()
+
+        with patch.object(
+            voice_routes,
+            "user_onboarding_complete",
+            AsyncMock(return_value=False),
+        ), patch.object(
+            voice_routes,
+            "user_has_consent",
+            AsyncMock(return_value=True),
+        ), patch.object(
+            voice_routes,
+            "_load_voice_session",
+            load_voice_session,
+        ):
+            session_id, voice, err, meta = await voice_routes._bind_session(
+                websocket,
+                _principal(profile_completed_at=None),
+            )
+
+        self.assertIsNone(session_id)
+        self.assertIsNone(voice)
+        self.assertEqual(err, "onboarding_required")
+        self.assertEqual(meta, {})
+        load_voice_session.assert_not_awaited()
+
+    async def test_bind_session_rejects_existing_session_without_consent(self) -> None:
+        websocket = FakeWebSocket()
+        websocket.query_params = {"session_id": SESSION_ID}
+        load_voice_session = AsyncMock()
+
+        with patch.object(
+            voice_routes,
+            "user_has_consent",
+            AsyncMock(return_value=False),
+        ), patch.object(
+            voice_routes,
+            "_load_voice_session",
+            load_voice_session,
+        ):
+            session_id, voice, err, meta = await voice_routes._bind_session(
+                websocket,
+                _principal(consent_at=None),
+            )
+
+        self.assertIsNone(session_id)
+        self.assertIsNone(voice)
+        self.assertEqual(err, "consent_required")
+        self.assertEqual(meta, {})
+        load_voice_session.assert_not_awaited()
+
     async def test_bind_session_explicit_preset_overrides_db_voice_map(self) -> None:
         websocket = FakeWebSocket()
         websocket.query_params = {"session_id": SESSION_ID, "preset": "soft-young-fem"}