fix(HEL-207): 收盘后改走日线，禁止误调 rt_k，回退旧快照记失败

将实时窗口与调度窗口统一到 15:05；盘后优先日线并补关闭盘后同步；沿用旧快照时 sync/job 记 failed。

Co-authored-by: Cursor <cursoragent@cursor.com>
Co-authored-by: multica-agent <github@multica.ai>

backend/jobs/service.py

@@ -46,4 +46,13 @@ class JobServiceMixin:
                 lambda: self.sync_dashboard(today),
                 {"trade_date": today, "trigger": "realtime-poll"},
             )
+        elif self._closing_snapshot_due(today, snapshot):
+            # 15:05 后改走日线生成当日快照；按分钟去重，避免日线未就绪时刷爆任务。
+            bucket = int(time.time() // 60)
+            self.jobs.submit(
+                "market.refresh",
+                f"closing:{today}:{bucket}",
+                lambda: self.sync_dashboard(today),
+                {"trade_date": today, "trigger": "post-close"},
+            )
         self._schedule_automatic_screeners(today, snapshot)