Fires one leg on one account through the scheduler's own fire path (sizing,
take-profit, daily-loss stop, exit bracket), overriding only the one-trade-
per-day rule for unsplit accounts. Flat, history, daily-loss room, trading
hours, a flat lane and the lane mutex still apply. The daily-loss check is
factored out so both paths share it.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
