[Feature] 请求支持证书申请后以发送邮件的方式部署

### Description / 功能描述

工作流编排时，在部署环节选择邮件发送方式，选择通知渠道里配置好的邮件类型，证书类型，填写接收人邮箱。证书申请成功后，按照配置把证书打包发送到指定邮箱

### Motivation / 请求动机

域名指向了第三方IP，需要提供域名证书供第三方自行部署。

### Miscellaneous / 其他

_No response_

### Contribution / 贡献代码

- [x] I am interested in contributing a PR for this! / 我乐意为此提交代码并发起 PR！

No files, tests, or entry points are named. Start by tracing the workflow deployment stage, configured notification channels, and the certificate-issuance success path. Done means users can select email delivery, an email type and certificate type, enter recipients, and receive the packaged certificate after successful issuance.

Written by the indexing model from the issue text.