[Feature] 支持Fastly CDN部署

### 功能描述 / Description

希望可以支持部署Fastly CDN，部署到证书夹中：


### 请求动机 / Motivation

Fastly CDN是和CloudFlare一样的国外cdn，但是每个月有500GB流量，支持cname接入，优化后国内速度比Cloudflare更快，但是证书仅仅支持2个免费续签证书，后面就需要付费或者自己上传了，希望可以支持Fastly CDN证书的部署。

### 其他 / Miscellaneous

首先，我不清楚开发者您是否用过Fastly CDN，所以我找了一篇写的比较全面的使用教程供您参考：
https://blog.ihwx.cn/archives/1745499509105

对于API部分，有官网API如下：https://www.fastly.com/documentation/reference/api/tls/platform/

几乎所有的api都在如下地址中提供：https://www.fastly.com/documentation/reference/api/

为了让您能更加方便的查看，我还找到了一个接口文档：https://www.postman.com/fastly/fastly-developer-hub/request/uqqucdq/update-a-certificate

希望能够帮助到作者适配，感谢作者的贡献，很喜欢您的项目！

### 贡献 / Contribution

- [ ] 我乐意为此贡献代码！ / I am interested in contributing to this issue!

No repository files, tests, or entry points are named. Start by reading Fastly's TLS Platform API documentation and the linked Postman request, then trace the project's existing certificate deployment integrations. Done means a Fastly CDN certificate can be deployed through the project with the required API behavior covered by appropriate tests.

Written by the indexing model from the issue text.