插件 MCP OAuth（camelCase）

不要抄 config.toml 的 client_id。callbackUrl 里的端口不会改监听口，要同时写 callbackPort。

{
  "mcpServers": {
    "sample": {
      "type": "http",
      "url": "https://mcp.example.com/mcp",
      "oauth": {
        "clientId": "my-pre-registered-client",
        "callbackUrl": "http://127.0.0.1:4321/callback/registered",
        "callbackPort": 4321
      }
    }
  }
}