fix: close broker uncertainty audit gaps

trex_core/application/execution.py

@@ -579,6 +579,7 @@ class ExecutionService:
             slot.slot_id,
             str(slot.broker_order_id),
             CancelState.UNKNOWN.value,
+            only_if_unset=True,
         ):
             _log.error(
                 "cancel attempt reservation conflict: slot=%s broker_order_id=%s",
@@ -719,6 +720,8 @@ class ExecutionService:
         if not slot.broker_order_id:
             # Claimed but not yet dispatched — execution loop will pick up or rollback.
             return "not_dispatched"
+        if slot.cancel_state is not None:
+            return "cancel_already_recorded"
         side = "buy" if slot.status is SlotState.PENDING_BUY else "sell"
         qty = int(slot.qty or 0)
         try:
@@ -735,8 +738,9 @@ class ExecutionService:
                 slot.slot_id,
                 str(slot.broker_order_id),
                 CancelState.UNKNOWN.value,
+                only_if_unset=True,
             ):
-                return "cancel_state_conflict"
+                return "cancel_already_recorded"
             outcome = self._broker.cancel_order(slot.broker_order_id, **cancel_kwargs)
         except Exception:  # noqa: BLE001 - adapter failure becomes durable unknown
             outcome = CancelOutcome(CancelState.UNKNOWN, "adapter_exception")