feat(roundtable): 业务链条配置增加管理员权限，管理员可配所有链条

- 后端 store/路由：scope=all（仅管理员）列全量；get/update/delete 加 is_admin 旁路，管理员可操作任意 owner 链条且不转移归属；非管理员请求 all 退化为 mine
- 前端列表页/会商弹窗：管理员多「全部链条」筛选 tab，canManage=isAdmin||isMine 放开发布/设置/删除
- 编辑器：管理员可见发布按钮；按 chainId 找不到本地列表时直接 getChain 拉取（修复管理员从「全部链条」进编辑器空白），并修掉自身无链条时加载卡死的边界

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

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

@@ -70,36 +70,41 @@ class RoundtableChainRepository:
         }
 
     async def list_chains(
-        self, user_id: str, *, scope: str = "mine", limit: int = 200
+        self, user_id: str, *, scope: str = "mine", limit: int = 200, is_admin: bool = False
     ) -> list[dict[str, Any]]:
         """列出链条。
 
         ``scope``:
           - ``"mine"``（默认）：仅当前用户自己的链条；
-          - ``"public"``：所有**已发布**（``is_public=True``）链条，含本人发布的。
+          - ``"public"``：所有**已发布**（``is_public=True``）链条，含本人发布的；
+          - ``"all"``：所有账号的全部链条（**仅管理员**，由路由层校验后传 ``is_admin=True``；
+            非管理员误传则按 ``"mine"`` 退化，绝不越权）。
         其余值按 ``"mine"`` 处理。``is_mine`` 标记每条是否本人所有，供前端判断可否编辑。
         """
         if scope == "public":
             cond = RoundtableChainRow.is_public.is_(True)
+        elif scope == "all" and is_admin:
+            cond = None
         else:
             cond = RoundtableChainRow.user_id == user_id
-        stmt = (
-            select(RoundtableChainRow)
-            .where(cond)
-            .order_by(RoundtableChainRow.updated_at.desc())
-            .limit(limit)
-        )
+        stmt = select(RoundtableChainRow)
+        if cond is not None:
+            stmt = stmt.where(cond)
+        stmt = stmt.order_by(RoundtableChainRow.updated_at.desc()).limit(limit)
         async with self._sf() as session:
             result = await session.execute(stmt)
             return [self._to_dict(row, user_id) for row in result.scalars()]
 
-    async def get_chain(self, chain_id: str, user_id: str) -> dict[str, Any] | None:
-        """取一条链条：owner 可见,**已发布的公共链条任何人可见**(供选入研讨)。"""
+    async def get_chain(
+        self, chain_id: str, user_id: str, *, is_admin: bool = False
+    ) -> dict[str, Any] | None:
+        """取一条链条：owner 可见,**已发布的公共链条任何人可见**(供选入研讨)；
+        **管理员可见任意链条**(``is_admin=True``，供后台管理配置)。"""
         async with self._sf() as session:
             row = await session.get(RoundtableChainRow, chain_id)
             if row is None:
                 return None
-            if row.user_id != user_id and not bool(getattr(row, "is_public", False)):
+            if not is_admin and row.user_id != user_id and not bool(getattr(row, "is_public", False)):
                 return None
             return self._to_dict(row, user_id)
 
@@ -140,10 +145,12 @@ class RoundtableChainRepository:
         seat_mode=_UNSET,
         gather_first=_UNSET,
         is_public=_UNSET,
+        is_admin: bool = False,
     ) -> dict[str, Any] | None:
         async with self._sf() as session:
             row = await session.get(RoundtableChainRow, chain_id)
-            if row is None or row.user_id != user_id:
+            # 管理员可改任意链条；否则仅 owner 本人。不变更 user_id（不转移归属）。
+            if row is None or (not is_admin and row.user_id != user_id):
                 return None
             if title is not _UNSET and title is not None:
                 row.title = str(title).strip()
@@ -168,10 +175,11 @@ class RoundtableChainRepository:
             await session.refresh(row)
             return self._to_dict(row, user_id)
 
-    async def delete_chain(self, chain_id: str, user_id: str) -> bool:
+    async def delete_chain(self, chain_id: str, user_id: str, *, is_admin: bool = False) -> bool:
         async with self._sf() as session:
             row = await session.get(RoundtableChainRow, chain_id)
-            if row is None or row.user_id != user_id:
+            # 管理员可删任意链条；否则仅 owner 本人。
+            if row is None or (not is_admin and row.user_id != user_id):
                 return False
             await session.delete(row)
             await session.commit()