perf: 去掉 handler 内层重复鉴权

鉴权只保留各路由 r.use 一次，受保护请求少一轮会话查库。

apps/server/src/routes/admin-engine.ts

@@ -31,8 +31,6 @@ export function adminEngineRoutes() {
       },
     }),
     async (c) => {
-      const guard = await requireAdminSession(c, async () => {});
-      if (guard) return guard;
       return c.json(engineStatus, 200);
     },
   );