feat: 会商链条启停与深度研究报告结构，并完善问答展示与 8BF 返回。

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

offline-backend-20260512/backend/packages/harness/deerflow/persistence/roundtable_chains/sql.py

@@ -62,6 +62,8 @@ class RoundtableChainRepository:
             "gather_first": bool(getattr(row, "gather_first", False)),
             # 发布状态 + 是否本人所有（前端据此显示「公共」徽标、决定能否编辑 / 发布）。
             "is_public": bool(getattr(row, "is_public", False)),
+            # 启停状态：缺省 True（存量行 / 补列前视为启用）。
+            "enabled": bool(getattr(row, "enabled", True)),
             "is_mine": (current_user_id is None) or (row.user_id == current_user_id),
             # 配置者（owner）的 user_id；路由层据此解析成可读用户名（owner_name）。
             "owner_id": row.user_id,
@@ -122,6 +124,7 @@ class RoundtableChainRepository:
             seat_mode=(data.get("seat_mode") or None),
             gather_first=bool(data.get("gather_first") or False),
             is_public=bool(data.get("is_public") or False),
+            enabled=True if data.get("enabled") is None else bool(data.get("enabled")),
             created_at=now,
             updated_at=now,
         )
@@ -145,6 +148,7 @@ class RoundtableChainRepository:
         seat_mode=_UNSET,
         gather_first=_UNSET,
         is_public=_UNSET,
+        enabled=_UNSET,
         is_admin: bool = False,
     ) -> dict[str, Any] | None:
         async with self._sf() as session:
@@ -170,6 +174,8 @@ class RoundtableChainRepository:
                 row.gather_first = bool(gather_first)
             if is_public is not _UNSET and is_public is not None:
                 row.is_public = bool(is_public)
+            if enabled is not _UNSET and enabled is not None:
+                row.enabled = bool(enabled)
             row.updated_at = datetime.now(UTC)
             await session.commit()
             await session.refresh(row)