feat(intents): dcy-011 buy intent portfolio_id 필수 계약 + ledger skip 가시화 (BAT-015)

dcy-011 전 주기 delivery. issue #6(buy 식별자 정정) + issue #11(ledger silent skip) 흡수.
거버넌스: 기존 Implemented REQ는 change-req, 신규 기능만 신규 REQ(OQ-3).

- REQ-007 (change-req): buy admission portfolio_id 필수화 + SnapshotStore symbol
  resolve + unknown_portfolio 거부 (hard cutover, OQ-1/OQ-2)
- REQ-021 (change-req): buy 메시지 payload symbol 제거
- REQ-018 (change-req): _record_ledger skip 가시화 (WARN + ledger_skipped 카운터)
- REQ-055 (신규): closed↔ledger_outbox anti-join 운영 점검 find_ledger_gap_slots

코드: intents.py(BuyIntent portfolio_id 필수 + resolve_symbol 주입 + _admit_buy
reject 분기), messaging_handlers.py, runtime/daemon.py(_resolve_symbol 배선),
execution.py(skip WARN 로그), adapters/persistence/ops_checks.py(신규 anti-join).

검증: 단위 282 passed/32 skipped, 인프라 게이트(PG+RabbitMQ) 314 passed, ruff clean.
BAT-015(standard) release-candidate. srs/index Next ID → REQ-056.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tests/adapters/messaging/test_rabbitmq_intent_e2e.py

@@ -52,7 +52,8 @@ def test_intent_admission_rpc_dedups_duplicate_correlation_id_over_rabbitmq(mq_u
     """REQ-023 AC-1: same correlation_id processed twice ⇒ slot transitions ONCE."""
     repo = InMemorySlotRepository()
     svc = SlotService(repo)
-    intents = IntentService(svc, repo, InMemoryIntentStore())
+    intents = IntentService(svc, repo, InMemoryIntentStore(),
+                            resolve_symbol=lambda pid: "005930")  # dcy-011: universe resolve
     svc.preallocate_daily_slots(DAY, 3)
     handler = make_intent_rpc_handler(intents)
 
@@ -77,7 +78,7 @@ def test_intent_admission_rpc_dedups_duplicate_correlation_id_over_rabbitmq(mq_u
         cid = "buy-dup-rmq"
         payload = {
             "intent_type": "buy", "intent_id": cid,
-            "trading_date": DAY.isoformat(), "symbol": "005930", "qty": 10,
+            "trading_date": DAY.isoformat(), "portfolio_id": "PF-1", "qty": 10,
         }
         r1 = client.call_rpc(queue, payload, correlation_id=cid, timeout=3.0)
         r2 = client.call_rpc(queue, payload, correlation_id=cid, timeout=3.0)