fix(api): GET /task 内存失后 DB fallback 返 status(治回测 done 后前端轮询 404 死循环卡等待) [nas]

sanguo_api/routes.py

@@ -131,10 +131,27 @@ async def submit_factor(req: FactorAnalysisRequest):
 @router.get("/task/{task_id}", dependencies=[Depends(verify_token)])
 def get_status(task_id: str):
     """Get task status"""
-    s = get_orchestrator().get_status(task_id)
+    orch = get_orchestrator()
+    s = orch.get_status(task_id)
     if s is None:
+        # 内存池无此 task(容器重启/已完成被清)→查 DB;有持久化结果则返其 status,
+        # 否则真不存在。治:done task 内存清后 GET /task 404 → 前端轮询死循环卡等待,
+        # 但结果其实在 DB(历史能查)。CTA/组合回测 done 后内存失均受益。
+        try:
+            from sanguo_backtest.result_store import load_result_by_task_id
+            if orch.db_path:
+                r = load_result_by_task_id(task_id, orch.db_path)
+                if r is not None:
+                    return {
+                        "task_id": task_id,
+                        "status": r.status or "done",
+                        "stage": "",
+                        "error_msg": None,
+                    }
+        except Exception:
+            pass
         raise HTTPException(status_code=404, detail="task not found")
-    pool = get_orchestrator().pool
+    pool = orch.pool
     stage = pool.get_stage(task_id)
     task = pool.get_task(task_id)
     return {