Fix unmanaged reconciliation review blockers

Co-authored-by: genichin <4282227+genichin@users.noreply.github.com>

trex_core/adapters/broker/ownership.py

@@ -17,6 +17,7 @@ from threading import Lock
 from trex_core.application.broker_port import (
     BalanceItem,
     BrokerBalanceError,
+    BrokerPort,
     CancelOutcome,
     FillStatus,
     OrderAck,
@@ -174,6 +175,9 @@ class OwnershipAwareBroker:
     def get_balance(self) -> list[BalanceItem]:
         return self._store.project(self._delegate.get_balance())
 
+    def authoritative_balance_reader(self) -> BrokerPort:
+        return self._delegate
+
     def exposes_full_balance_snapshot(self) -> bool:
         """False: projected balances omit operator-owned/unmanaged broker positions."""
         return False