doocs/md ? reverse-engineered prompt

I want to build a web-based Markdown editor specifically for creating beautiful WeChat articles. The main goal is to make a tool that's super clean and simple, so I can stop worrying about formatting. A user should be able to just write in Markdown and the app will instantly render a preview that's perfectly styled and ready to copy-paste into WeChat.

It should support all the standard Markdown syntax, but also advanced stuff like math formulas and diagrams (like Mermaid charts). A really important feature is flexible image hosting. Let users connect to different image storage services like GitHub, AWS S3, Cloudflare R2, or other cloud providers. The editor should also have some nice touches like customizable themes, different code highlighting styles, and maybe even an integrated AI assistant to help with writing and editing. It should feel like a modern, complete tool for content creators.