Deliver BAT-004: broker execution + KIS adapter + durable handoff

Implement REQ-011~015 (dcy-003): the order-execution layer on top of the
BAT-002 slot-core daemon, connecting intents to real orders.
- application: BrokerPort (submit/poll_fill/cancel) + ExecutionService
  (claim -> submit -> poll -> transition -> rollback -> reconcile)
- adapters/broker: PaperBroker (deterministic async double) and KISBroker
  (KIS Open API: token, order-cash, inquire-daily-ccld, cancel; VTS sandbox
  tr_ids; live account gated behind allow_live)
- persistence: option-A execution queue (find_pending_for_dispatch FOR
  UPDATE SKIP LOCKED, mark_dispatched idempotency guard, clear_dispatch)
- runtime: background execution loop in the daemon lifespan + startup
  reconcile; config selects paper|kis

Verification (real KIS VTS 모의투자 + PostgreSQL): 92 passed, ruff clean,
domain import sweep shows zero broker/web/db deps, buy->holding /
sell->closed / reject->idle, idempotent dispatch (exactly one order),
reconcile after crash creates no duplicate order, KIS sandbox token+submit
round-trip, and a daemon E2E through the background loop. Align the four
baseline docs. BAT-004 -> release-candidate; REQ-011~015 -> Implemented.

KIS live-account go-live, partial-fill accrual, option-B outbox, connection
pooling, and the safety floor remain deferred to follow-up Discoveries.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

trex_core/runtime/config.py

@@ -1,8 +1,9 @@
-"""Daemon configuration resolution (REQ-005, REQ-010)."""
+"""Daemon configuration resolution (REQ-005, REQ-010, REQ-012/013)."""
 from __future__ import annotations
 
 import os
 from dataclasses import dataclass
+from typing import Optional
 
 
 def _load_dotenv() -> None:
@@ -19,12 +20,25 @@ def _load_dotenv() -> None:
     load_dotenv(find_dotenv(usecwd=True), override=False)
 
 
+@dataclass(frozen=True)
+class KISConfig:
+    base_url: str
+    app_key: str
+    app_secret: str
+    account_ref: str
+    timeout: float
+    allow_live: bool
+
+
 @dataclass(frozen=True)
 class DaemonConfig:
     dsn: str
     total_slots: int
     host: str
     port: int
+    broker: str                      # 'paper' | 'kis'
+    execution_interval_sec: float
+    kis: Optional[KISConfig] = None
 
     @staticmethod
     def from_env() -> "DaemonConfig":
@@ -34,9 +48,23 @@ class DaemonConfig:
             raise RuntimeError(
                 "TREX_POSTGRESQL_DSN is required to start the slot-core daemon."
             )
+        broker = os.environ.get("TREX_BROKER", "paper").strip().lower()
+        kis: Optional[KISConfig] = None
+        if broker == "kis":
+            kis = KISConfig(
+                base_url=os.environ["TREX_KIS_BROKER_BASE_URL"],
+                app_key=os.environ["TREX_KIS_BROKER_APP_KEY"],
+                app_secret=os.environ["TREX_KIS_BROKER_APP_SECRET"],
+                account_ref=os.environ["TREX_KIS_BROKER_ACCOUNT_REF"],
+                timeout=float(os.environ.get("TREX_KIS_BROKER_TIMEOUT", "5")),
+                allow_live=os.environ.get("TREX_KIS_ALLOW_LIVE", "").lower() in ("1", "true", "yes"),
+            )
         return DaemonConfig(
             dsn=dsn,
             total_slots=int(os.environ.get("TREX_TOTAL_SLOTS", "10")),
             host=os.environ.get("TREX_API_HOST", "127.0.0.1"),
             port=int(os.environ.get("TREX_API_PORT", "8080")),
+            broker=broker,
+            execution_interval_sec=float(os.environ.get("TREX_EXECUTION_INTERVAL_SEC", "1.0")),
+            kis=kis,
         )