[WebSocket]服务端WebSocket使用AsyncClose()主动关闭连接时引发NullReferenceException异常

### 组件

WebSocket

### 版本号

3.0.25

### .NET SDK

.NET6

### 项目类型

Console

### 操作系统

Windows 11

### 运行环境

开发环境 (Development)

### 这个问题是否已经存在？

- [x] 我已经搜索过现有的问题 (https://gitee.com/RRQM_Home/TouchSocket/issues)

### 如何复现

在HttpService中创建websocket服务器。对Online的IWebSocket进行CloseAsync()会引发NullReferenceException

对于下面提供的demo仓库中的最小复现代码：
1. 启动程序
2. apifox连接ws://127.0.0.1:11451/ws, 并发送任意文本
3. 控制台打印错误

### 预期结果

对一个Online的IWebSocket进行CloseAsync()不会引发异常

### 实际结果

对一个Online的IWebSocket进行CloseAsync()报错

### 异常信息

## 异常信息:

```csharp
System.NullReferenceException: Object reference not set to an instance of an object.
  at TouchSocket.Http.WebSockets.InternalWebSocket.CloseAsync(WebSocketCloseStatus closeStatus, String statusDescription) in D:\OpenCode\TouchSocketPro\Src\TouchSocket.Http\WebSockets\Common\InternalWebSocket.cs:line 79
  at TouchSocketTest.WebSocketTestPlugin.OnWebSocketReceived(IWebSocket webSocket, WSDataFrameEventArgs e) in E:\workspace\MCSLTeam\touch-socket-exception-demo\TouchSocketTest\WebSocketTestPlugin.cs:line 18

```

## 截图:
  ![图1](https://foruda.gitee.com/images/1744726201993541420/2cb7eeec_7835431.png "屏幕截图")

## 调用过程:

```csharp
using TouchSocket.Core;
using TouchSocket.Http.WebSockets;

namespace TouchSocketTest;

public class WebSocketTestPlugin : PluginBase, IWebSocketReceivedPlugin
{
    public async Task OnWebSocketReceived(IWebSocket webSocket, WSDataFrameEventArgs e)
    {
        if (e.DataFrame.IsText)
        {
            await webSocket.SendAsync(e.DataFrame.ToText());
        }

try
        {
            // 使用CloseAsync关闭连接, 会报错: NullReferenceException
            await webSocket.CloseAsync(string.Empty);
        }
        catch (Exception exception)
        {
            Console.WriteLine(exception);
            throw;
        }
        
        // await e.InvokeNext();
    }
}
```
代码执行到
```csharp 
webSocket.CloseAsync(string.Empty)
```
时, 会执行到[InternalWebSocket::CloseAsync(WebSocketCloseStatus closeStatus, string statusDescription)](https://gitee.com/RRQM_Home/TouchSocket/blob/master/src/TouchSocket.Http/WebSockets/Common/InternalWebSocket.cs#L57)。
在

```csharp
// 第79行
await this.m_httpClientBase.ShutdownAsync(System.Net.Sockets.SocketShutdown.Both);
```

处因为this.m_httpClientBase为null而引发空指针异常, [(代码导航)](https://gitee.com/RRQM_Home/TouchSocket/blob/master/src/TouchSocket.Http/WebSockets/Common/InternalWebSocket.cs#L79)。

## 可能的解决方案

[InternalWebSocket](https://gitee.com/RRQM_Home/TouchSocket/blob/master/src/TouchSocket.Http/WebSockets/Common/InternalWebSocket.cs)的2种构造函数可能分别对应WebSocket客户端和服务端的构造函数, 这导致字段m_httpClientBase和m_httpSocketClient二者不会同时被赋值, 但是字段m_isServer提供了判断依据, 因此我认为可能的解决方案如下（可能有不对的地方）:

将

```csharp
internal sealed partial class InternalWebSocket : IWebSocket
{
    private readonly HttpClientBase m_httpClientBase;
    private readonly HttpSessionClient m_httpSocketClient;
    private readonly bool m_isServer;
    
    // ...
    public async Task CloseAsync(WebSocketCloseStatus closeStatus, string statusDescription)
    {
        // ...
        // 第79行开始
        await this.m_httpClientBase.ShutdownAsync(System.Net.Sockets.SocketShutdown.Both);
        await this.m_httpClientBase.SafeCloseAsync(statusDescription).ConfigureAwait(EasyTask.ContinueOnCapturedContext);

await this.m_httpSocketClient.ShutdownAsync(System.Net.Sockets.SocketShutdown.Both);
        await this.m_httpSocketClient.SafeCloseAsync(statusDescription).ConfigureAwait(EasyTask.ContinueOnCapturedContext);
    }
    // ...
}
```

更改为

```csharp
internal sealed partial class InternalWebSocket : IWebSocket
{
    private readonly HttpClientBase m_httpClientBase;
    private readonly HttpSessionClient m_httpSocketClient;
    private readonly bool m_isServer;
    
    // ...
    public async Task CloseAsync(WebSocketCloseStatus closeStatus, string statusDescription)
    {
        // ...
        // 第79行开始
        if (this.m_isServer)
        {
            await this.m_httpSocketClient.ShutdownAsync(System.Net.Sockets.SocketShutdown.Both);
            await this.m_httpSocketClient.SafeCloseAsync(statusDescription).ConfigureAwait(EasyTask.ContinueOnCapturedContext);
        }
        else 
        {
            await this.m_httpClientBase.ShutdownAsync(System.Net.Sockets.SocketShutdown.Both);
            await this.m_httpClientBase.SafeCloseAsync(statusDescription).ConfigureAwait(EasyTask.ContinueOnCapturedContext);
        }
    }
    // ...
}
```

### Demo 地址（仅限Git地址）

https://gitee.com/ares_connor/touch-socket-exception-demo

### 承诺支持

- [x] 我确定我已经对TouchSocket项目进行了“Star”操作。

### 承诺规范

- [x] 我确定已完整阅读[Issue提问规范](https://touchsocket.net/docs/current/troubleshootissue)，并按照要求填写。

### 承诺友好

- [x] 我承诺将本着相互尊重、理解和友善的态度进行交流，共同维护好 TouchSocket 来之不易的良好的社区氛围。

GVP 若汝棋茗/TouchSocket

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GVP若汝棋茗/TouchSocket

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