Fix target-exit mismatch: correct close reason and executable PnL gate.

Locked premium exits no longer label as fixed_usdt; mark/book optimism no longer triggers close into a realized loss.

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

backend/app/strategy/engine.py

@@ -882,6 +882,17 @@ class StrategyEngine:
                 locked_exit_target=locked_exit,
             )
             pending_close = st["phase"] in ("liquidity_wait", "closing")
+            # 曾因达标进入流动性等待，但当前估价已跌破目标：取消挂起，避免硬平出亏损却仍记「达标」
+            if (
+                pending_close
+                and not expired.should_close
+                and not decision.should_close
+            ):
+                self._set_state(
+                    phase="open",
+                    last_error="达标后流动性等待期间浮盈回落，已取消平仓挂起",
+                )
+                return
             if expired.should_close or decision.should_close or pending_close:
                 is_oo = (
                     str(upl.get("hedge_mode") or "") == "option_option"

backend/app/strategy/exits.py

@@ -110,16 +110,17 @@ def check_exits(
     locked_exit_target: float | None = None,
 ) -> ExitDecision:
     """净盈利（预估全平后）≥ 所选模式目标则全平。持仓锁定目标优先。"""
+    # 模式始终按设置解析（权利金倍数 vs 固定），勿因锁定目标就改成 fixed_usdt
+    _resolved_target, mode = resolve_exit_target(
+        exit_mode=exit_mode,
+        net_profit_target=net_profit_target,
+        premium_exit_multiple=premium_exit_multiple,
+        initial_premium=initial_premium,
+    )
     if locked_exit_target is not None and float(locked_exit_target) > 0:
         target = float(locked_exit_target)
-        mode = EXIT_MODE_FIXED
     else:
-        target, mode = resolve_exit_target(
-            exit_mode=exit_mode,
-            net_profit_target=net_profit_target,
-            premium_exit_multiple=premium_exit_multiple,
-            initial_premium=initial_premium,
-        )
+        target = float(_resolved_target)
     if target > 0 and net_pnl + 1e-9 >= target:
         reason = "premium_multiple" if mode == EXIT_MODE_PREMIUM else "fixed_usdt"
         return ExitDecision(True, reason, target)