- Fixes a 1.30+ regression in connection stability for exec / attach / portforward requests initiated using a websocket client ([#130253](https://github.com/kubernetes/kubernetes/pull/130253), [@fuweid](https://github.com/fuweid)) [SIG API Machinery, CLI and Testing]

* kube-apiserver: fixed a bug that could cause a goroutine leak if the apiserver encountered an encoding error serving a watch to a websocket watcher ([#84693](https://github.com/kubernetes/kubernetes/pull/84693), [@tedyu](https://github.com/tedyu))

* kube-apiserver: fixed a bug that could cause a goroutine leak if the apiserver encountered an encoding error serving a watch to a websocket watcher ([#84693](https://github.com/kubernetes/kubernetes/pull/84693), [@tedyu](https://github.com/tedyu))

* HTTP Caching- [RFC 9111](https://datatracker.ietf.org/doc/html/rfc9111)
* HTTP/1.1 - [RFC 9112](https://datatracker.ietf.org/doc/html/rfc9112)
* HTTP/2 - [RFC 9113](https://datatracker.ietf.org/doc/html/rfc9113)
* Websockets - [RFC 6455](https://datatracker.ietf.org/doc/html/rfc6455)
* SSE - [Server-sent events](https://html.spec.whatwg.org/multipage/server-sent-events.html#server-sent-events)

- Fixes issue with websocket-based watches of Service objects not closing correctly on timeout ([#102541](https://github.com/kubernetes/kubernetes/pull/102541), [@liggitt](https://github.com/liggitt)) [SIG API Machinery and Testing]

## Dependencies

- Enabled feature gates for PortForward (kubectl port-forward) over WebSockets by default (beta).
   - Server-side feature gate: PortForwardWebsocket
   - Client-side (kubectl) feature gate: PORT_FORWARD_WEBSOCKETS environment variable

    val e = InterruptedIOException("timeout")
    if (cause != null) e.initCause(cause)
    return e
  }

  /**
   * Stops applying the timeout before the call is entirely complete. This is used for WebSockets
   * and duplex calls where the timeout only applies to the initial setup.
   */
  fun timeoutEarlyExit() {
    check(!timeoutEarlyExit)
    timeoutEarlyExit = true
    timeout.exit()
  }

  /**

  pods in lower QoS tiers.
  ([#41149](https://github.com/kubernetes/kubernetes/pull/41149),
  [@sjenning](https://github.com/sjenning))
* Port forwarding can forward over websockets or SPDY.
  ([#33684](https://github.com/kubernetes/kubernetes/pull/33684),
  [@fraenkel](https://github.com/fraenkel))
* Flag gate faster evictions based on node memory pressure using kernel memcg