Fix OKX abandon residual double-book and fill/residual ledger holes.

After dual-close leaves option pending, continue close_group instead of false residual; reject partial fills on wait timeout; LIVE residual settle allow_negative.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/app/sim/matcher.py

@@ -854,11 +854,15 @@ class Matcher:
         opt_qty = float(row["option_qty_eth"])
         opt_pnl = (of.fill_px - opt_entry) * opt_qty
         opt_cash = of.notional - of.fee
+        from ..config import get_settings
+
         self.ledger.apply_cash(
             opt_cash,
             kind="close_option",
             group_id=group_id,
             note=f"residual option expiry settle{' force' if force else ''}",
+            # LIVE 本地账本仅镜像；拒记会导致 residual 永久 pending
+            allow_negative=not get_settings().is_sim,
         )
 
         with self.db._lock: