[Bug] Office365 STARTTLS 无法发送邮件 显示TLS失败

### Release Version / 软件版本

v0.4.9

### Description / 缺陷描述

无法发送 测试发送的时候显示

```shell
failed to send mail: dial failed: tls: first record does not look like a TLS handshake
```

### Steps to reproduce / 复现步骤

使用一个office365的邮箱链接就会显示，但是可以连接的
```shell
root@xxxx:~# telnet smtp.office365.com 587
Trying 2603:1046:c03:e::2...
Connected to smtp.office365.com.
Escape character is '^]'.
220 KL1PR0401CA0023.outlook.office365.com Microsoft ESMTP MAIL Service ready at Thu, 18 Dec 2025 14:47:50 +0000
```