残留批次A：成员删除、PR needs_local_worker 落库、推送 DNS TOCTOU

- 成员删除：DELETE /projects/{id}/members/{user_id}，限 owner 或
  全局管理员，禁删唯一 owner，记 remove_member 审计
  （AuthStore.remove_member + server 分发，沿用 PATCH 守卫口径）
- PR needs_local_worker 落库：非 local 扫到 queued 任务时 CAS
  写行状态为 needs_local_worker；claim/find_open 同步认该状态，
  标记过的行仍可被 local worker 认领、不被搁置；另修
  claim/find_open 对裸 sqlite3 tuple 行的 dict() 兜底
  （TypeError/ValueError）
- 推送 DNS TOCTOU：发送改走建连时解析+判段的连接类，解析
  一次、只拨判过的 IP，Host/SNI 仍为原域名；opener 直接构造
  以排除 ProxyHandler 改写（build_opener 默认会塞代理）

cloud/server.py

@@ -2471,6 +2471,54 @@ class CloudControlPlaneHandler(BaseHTTPRequestHandler):
         self._send_json(200, {"project_id": project_id,
                               "user_id": target, "role": role})
 
+    def _project_member_delete(self, user_id, project_id, target):
+        """DELETE /projects/{id}/members/{user_id}：限项目 owner
+        或全局管理员。删唯一 owner 时 409（否则项目将无 owner
+        可管）；目标非成员时 404。成功记 remove_member 审计。"""
+        if not self._project_exists(project_id):
+            self._send_json(404, {"error": "project not found"})
+            return
+        if not self._can_manage_members(user_id, project_id):
+            self._send_json(403, {"error": "forbidden"})
+            return
+        with _auth_store(self.server.db_path) as store:
+            cur = store.conn.execute(
+                "SELECT role FROM project_members"
+                " WHERE project_id = ? AND user_id = ?",
+                (project_id, target)).fetchone()
+            if cur is None:
+                self._send_json(404, {"error": "member not found"})
+                return
+            if cur[0] == "owner":
+                owners = store.conn.execute(
+                    "SELECT COUNT(*) FROM project_members"
+                    " WHERE project_id = ? AND role = 'owner'",
+                    (project_id,)).fetchone()[0]
+                if owners <= 1:
+                    self._send_json(
+                        409,
+                        {"error": "cannot remove the only owner"})
+                    return
+            self._remove_member_row(store, project_id, user_id, target)
+        self._send_json(200, {"project_id": project_id,
+                              "user_id": target})
+
+    def _remove_member_row(self, store, project_id, actor_id, target_id):
+        """删成员行并记审计：owner 走 AuthStore.remove_member
+        （内含 owner 校验与审计）；非成员的全局管理员走直接删
+        + 同格式审计（remove_member 的 owner 校验会挡住全局
+        管理员，故分流，与 _set_member_row 同款）。"""
+        if store.check_permission(actor_id, project_id,
+                                  "manage_project"):
+            store.remove_member(project_id, actor_id, target_id)
+            return
+        store.conn.execute(
+            "DELETE FROM project_members"
+            " WHERE project_id = ? AND user_id = ?",
+            (project_id, target_id))
+        store.conn.commit()
+        store.audit(actor_id, project_id, "remove_member", target_id)
+
     # -- 项目子资源：记忆 / 知识库 / 成本 -------------------------------
     def _project_exists(self, project_id):
         conn = self._db()
@@ -2510,10 +2558,12 @@ class CloudControlPlaneHandler(BaseHTTPRequestHandler):
             else:
                 self._send_json(404, {"error": "not found"})
             return
-        # /projects/{id}/members/{user_id}：PATCH 改角色
+        # /projects/{id}/members/{user_id}：PATCH 改角色 / DELETE 删成员
         if len(parts) == 3 and parts[1] == "members":
             if method == "PATCH":
                 self._project_member_patch(user_id, project_id, parts[2])
+            elif method == "DELETE":
+                self._project_member_delete(user_id, project_id, parts[2])
             else:
                 self._send_json(404, {"error": "not found"})
             return