Fix semi open stalls: one-leg asks, OTM realign, clearer pick errors.

Monitor no longer shows ATM Put bias while semi-auto is authorized for Call.

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

backend/app/strategy/engine.py

@@ -1238,9 +1238,17 @@ class StrategyEngine:
                     return
             except Exception:
                 pass
-            self._set_state(
-                last_error="无合格期权：需剩余时长、杠杆（及已开启的ATM偏差）同时满足"
-            )
+            pick_why = None
+            try:
+                pick_why = get_session().last_pick_fail_reason()
+            except Exception:
+                pick_why = None
+            if pick_why:
+                self._set_state(last_error=f"无合格期权：{pick_why}")
+            else:
+                self._set_state(
+                    last_error="无合格期权：需剩余时长、杠杆（及已开启的ATM偏差）同时满足"
+                )
             return
 
         # 半自动：选约异步窗口后再次确认授权，防止取消授权后仍开仓