sse timeout set dont work & always close after 5mins

Describe the bug
always res.on('close') tigger when 5mins after.

To Reproduce

app.get('/sse', async (req, res) => {
  // Create SSE transport for legacy clients
  const transport = new SSEServerTransport('/messages', res);
  transports.sse[transport.sessionId] = transport;
  
  res.on("close", () => {
    delete transports.sse[transport.sessionId];
  });
  
  await server.connect(transport);
});

Expected behavior
to set a bigger timeout

callTool(xx,undefined, {timeout: 20mins})

but dont work

Start at the SSEServerTransport entry point and trace how the connection close and timeout are handled for the reproduced /sse route. Check how the callTool timeout option is passed, then reproduce the five-minute disconnect and verify that a larger timeout keeps the SSE connection open as expected.