fix(broker): enforce operator broker truth boundary

trex_core/adapters/broker/kis.py

@@ -18,6 +18,7 @@ import httpx
 
 from trex_core.application.broker_port import (
     BalanceItem,
+    BrokerBalanceError,
     FillStatus,
     OrderAck,
     OrderRequest,
@@ -285,8 +286,9 @@ class KISBroker:
         """KIS 주식잔고조회 (`TTTC8434R`/`VTTC8434R`).
 
         Aggregates `output1[*].pdno` + `hldg_qty`, drops zero-qty rows
-        (D-2 leftover, Design Decision 7). Network/credential errors map to
-        an empty list (caller treats as no broker positions).
+        (D-2 leftover, Design Decision 7). Only a validated `rt_cd=0` response
+        may return an empty list; token/HTTP/shape/KIS failures raise a sanitized
+        :class:`BrokerBalanceError` so reconciliation cannot infer false zero.
         """
         cano, product = self._account()
         tr_id = "VTTC8434R" if self._mock else "TTTC8434R"
@@ -298,21 +300,44 @@ class KISBroker:
             "PRCS_DVSN": "01",
             "CTX_AREA_FK100": "", "CTX_AREA_NK100": "",
         }
+        try:
+            headers = self._headers(tr_id)
+        except (httpx.HTTPError, KeyError, TypeError, ValueError):
+            # Token issuance/header construction is distinct from a rejected
+            # balance endpoint response and must never look like an empty book.
+            raise BrokerBalanceError("token_issuance_failed") from None
         try:
             resp = httpx.get(
                 f"{self._base_url}/uapi/domestic-stock/v1/trading/inquire-balance",
-                headers=self._headers(tr_id), params=params, timeout=self._timeout,
+                headers=headers, params=params, timeout=self._timeout,
             )
+            resp.raise_for_status()
             payload = resp.json()
-        except (httpx.HTTPError, ValueError):
-            return []
+        except httpx.HTTPStatusError as exc:
+            status = exc.response.status_code if exc.response is not None else None
+            code = "authentication_failed" if status == 401 else (
+                "authorization_failed" if status == 403 else "transport_failed"
+            )
+            raise BrokerBalanceError(code) from None
+        except httpx.HTTPError:
+            raise BrokerBalanceError("transport_failed") from None
+        except (ValueError, TypeError):
+            raise BrokerBalanceError("malformed_response") from None
+        if not isinstance(payload, dict):
+            raise BrokerBalanceError("malformed_response")
         if str(payload.get("rt_cd")) != "0":
-            return []
-        rows = payload.get("output1") or []
+            raise BrokerBalanceError("broker_rejected")
+        rows = payload.get("output1")
+        if not isinstance(rows, list):
+            raise BrokerBalanceError("malformed_response")
         out: list[BalanceItem] = []
         for row in rows:
+            if not isinstance(row, dict):
+                raise BrokerBalanceError("malformed_response")
             symbol = str(row.get("pdno") or "").strip()
-            qty = _safe_int(row.get("hldg_qty")) or 0
+            qty = _safe_int(row.get("hldg_qty"))
+            if qty is None:
+                raise BrokerBalanceError("malformed_response")
             if not symbol or qty <= 0:
                 continue
             out.append(BalanceItem(symbol=symbol, hldg_qty=qty))

trex_core/adapters/persistence/postgresql.py

@@ -134,6 +134,18 @@ class PostgreSQLSlotRepository:
                 )
                 return [self._row_to_slot(r) for r in cur.fetchall()]
 
+    def find_managed_slot_by_symbol(self, instance_key: str, symbol: str) -> Optional[Slot]:
+        with self._psycopg.connect(self._dsn) as conn:
+            with conn.cursor() as cur:
+                cur.execute(
+                    f"SELECT {_SLOT_COLUMNS} FROM daily_slot "
+                    "WHERE instance_key = %s AND symbol = %s "
+                    "ORDER BY updated_at DESC NULLS LAST, slot_id ASC LIMIT 1",
+                    (instance_key, symbol),
+                )
+                row = cur.fetchone()
+                return self._row_to_slot(row) if row else None
+
     def reconcile_universe(
         self, instance_key: str, universe: dict[str, str],
         *, allow_retire: bool = True,