feat: 持仓委托改止盈止损，保证金改读CTP柜台UseMargin

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

install_trading.py

@@ -488,6 +488,15 @@ def install_trading(app, *, login_required, require_nav, get_db, get_setting, se
             direction, entry, sl if sl is not None else entry,
             tp if tp is not None else entry, lots, mark, capital, sym,
         )
+        ctp_margin = float(ctp.get("margin") or 0) if ctp else 0.0
+        est_margin = pos_metrics.get("margin")
+        margin = ctp_margin if ctp_margin > 0 else est_margin
+        margin_source = "ctp" if ctp_margin > 0 else "estimate"
+        position_pct = (
+            round(float(margin) / capital * 100, 2)
+            if capital > 0 and margin
+            else pos_metrics.get("position_pct")
+        )
         order_st = monitor_order_status(
             mon or {}, mode=mode, ths_code=sym, direction=direction,
         )
@@ -529,8 +538,9 @@ def install_trading(app, *, login_required, require_nav, get_db, get_setting, se
             "holding_duration": holding or None,
             "mark_price": mark,
             "current_price": mark,
-            "margin": pos_metrics.get("margin"),
-            "position_pct": pos_metrics.get("position_pct"),
+            "margin": margin,
+            "margin_source": margin_source,
+            "position_pct": position_pct,
             "risk_amount": pos_metrics.get("risk_amount") if sl is not None else None,
             "risk_pct": pos_metrics.get("risk_pct") if sl is not None else None,
             "rr_ratio": pos_metrics.get("rr_ratio") if sl is not None and tp is not None else None,