tests/services/test_broker_doubles_surface.py:219: in test_harness_short_with_limit_takes_limit_branch_not_market
    assert result.children, "submit returned no children"
E   AssertionError: submit returned no children
E   assert []
E    +  where [] = ExecutionResult(request=ExecutionRequest(symbol='TZA', side=<Side.SHORT: 'short'>, qty=100, amount=0.0, tactic=<Tactic.MARKET: 'market'>, urgency=<Urgency.IMMEDIATE: 'immediate'>, deadline=None, allow_llm=False, limit_price=5.79, client_order_id='contract-test-short-tza-cuixia-001-20260730T100000', dispatch='contract-probe', account_nick='cuixia', decision_ts=datetime.datetime(2026, 7, 30, 15, 17, 0, 536977, tzinfo=datetime.timezone.utc), request_ts=datetime.datetime(2026, 7, 30, 15, 17, 0, 536979, tzinfo=datetime.timezone.utc), n_chunks=1, chunk_delay_seconds=5.0, allow_fractional=False, origin='test', extra={}), status='error', filled_qty=0.0, residual_qty=0.0, children=[], error='broker_paused_remaining_day', started_at=datetime.datetime(2026, 7, 30, 15, 17, 0, 611295, tzinfo=datetime.timezone.utc), finished_at=datetime.datetime(2026, 7, 30, 15, 17, 0, 611260, tzinfo=datetime.timezone.utc), tactic_used='paused', fallback_reason='broker_paused_remaining_day', broker_response=None).children