fix: 任务抽屉产出结果优化 + server 启动修复

- 任务抽屉产出结果 tab 优先显示 last_message（日志消息），
  过滤 result_data 中的 None/空值
- 修复 tasks.py 因 opencode 块删除导致的 SyntaxError
- 修复 scheduled_generate 存储 None 值问题
- 清理 DB 中旧 scheduled_refresh_search_cache 的 56 条
  TaskLog + 1 条 TaskConfig
- 更新 PROGRESS.md

platform/backend/app/core/scheduler.py

@@ -262,7 +262,7 @@ class TaskScheduler:
                     logger.info("[Scheduled] Review completed for %s", created_id)
             _log_task("scheduled_generate", "success", log_id=log_id,
                       message=f"创作完成" + (f", 选题 {created_id}" if created_id else ""),
-                      result_data={"topic_id": created_id, "review_ok": review_result.get("ok") if review_result else None},
+                      result_data={"topic_id": created_id} if created_id else {"note": "无待生成的选题"},
                       started_at=started, finished_at=datetime.now(timezone.utc))
         except Exception as e:
             _log_task("scheduled_generate", "failed", log_id=log_id,