feat: add kill-switch control flow

trex_core/adapters/portfolio/killswitch_store.py

@@ -0,0 +1,52 @@
+"""PostgreSQL-backed day-scoped kill-switch exclusion store (REQ-044 / BAT-012).
+
+Distinct from `PostgreSQLPauseStore`: pause is permanent (resume-until),
+kill-switch exclusion is day-scoped — keyed by `(portfolio_id, trading_date)`
+so the next trading day is automatically clear (reads filter by trading_date).
+`portfolio_id == "*"` is the global-exclusion sentinel.
+"""
+from __future__ import annotations
+
+from datetime import date
+from typing import Any
+
+from trex_core.adapters.persistence.postgresql import _require_psycopg
+from trex_core.application.portfolio import GLOBAL_KILLSWITCH  # noqa: F401  (re-export)
+
+
+class PostgreSQLKillSwitchStore:
+    """`killswitch_exclusion` table CRUD. (portfolio_id, trading_date) PK."""
+
+    def __init__(self, dsn: str, *, psycopg_module: Any = None) -> None:
+        self._psycopg = _require_psycopg(psycopg_module)
+        self._dsn = dsn
+
+    def exclude(self, portfolio_id: str, trading_date: date, *, actor: str = "kill-switch") -> None:
+        with self._psycopg.connect(self._dsn, autocommit=False) as conn:
+            with conn.cursor() as cur:
+                cur.execute(
+                    "INSERT INTO killswitch_exclusion (portfolio_id, trading_date, actor) "
+                    "VALUES (%s, %s, %s) "
+                    "ON CONFLICT (portfolio_id, trading_date) DO NOTHING",
+                    (portfolio_id, trading_date, actor),
+                )
+                conn.commit()
+
+    def clear(self, portfolio_id: str, trading_date: date) -> None:
+        with self._psycopg.connect(self._dsn, autocommit=False) as conn:
+            with conn.cursor() as cur:
+                cur.execute(
+                    "DELETE FROM killswitch_exclusion "
+                    "WHERE portfolio_id = %s AND trading_date = %s",
+                    (portfolio_id, trading_date),
+                )
+                conn.commit()
+
+    def list_excluded(self, trading_date: date) -> set[str]:
+        with self._psycopg.connect(self._dsn) as conn:
+            with conn.cursor() as cur:
+                cur.execute(
+                    "SELECT portfolio_id FROM killswitch_exclusion WHERE trading_date = %s",
+                    (trading_date,),
+                )
+                return {row[0] for row in cur.fetchall()}