Refresh perp mark from public ticker when position metrics are unavailable.

Sim/no-keys mode was falling back to entry so 标记 stayed frozen at open price.

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

lib/hedge_plan/hedge_plan_book_lib.py

@@ -105,6 +105,36 @@ def perp_close_book_side(position_side: str) -> str:
     return "bids" if str(position_side or "").lower() == "long" else "asks"
 
 
+def fetch_perp_mark_px(exchange: Any, symbol: str) -> Optional[float]:
+    """公开行情标记价:优先 markPx,其次 last / 买卖中间价.模拟盘无持仓 metrics 时用此刷新标记."""
+    sym = str(symbol or "").strip()
+    if not sym or exchange is None or not hasattr(exchange, "fetch_ticker"):
+        return None
+    try:
+        t = exchange.fetch_ticker(sym) or {}
+        info = t.get("info") if isinstance(t.get("info"), dict) else {}
+        for v in (
+            info.get("markPx"),
+            t.get("mark"),
+            t.get("last"),
+            info.get("last"),
+        ):
+            px = _sf(v)
+            if px is not None and px > 0:
+                return float(px)
+        bid = _sf(t.get("bid") or info.get("bidPx"))
+        ask = _sf(t.get("ask") or info.get("askPx"))
+        if bid and ask and bid > 0 and ask > 0:
+            return float((bid + ask) / 2.0)
+        if bid and bid > 0:
+            return float(bid)
+        if ask and ask > 0:
+            return float(ask)
+    except Exception:
+        return None
+    return None
+
+
 def fetch_perp_close_vwap(
     exchange: Any,
     *,