marp-team/marp ? reverse-engineered prompt

I want to build a tool that lets you create slide presentations from plain Markdown files. The user experience should be super simple: just write your content and separate slides with a --- horizontal rule. It should come with some nice default themes to make the slides look good out of the box.

The most important part is being able to export the presentation. I'll need a command-line tool that can take a .md file and convert it into a standalone HTML file, a PDF document, and even a PowerPoint (PPTX) file, so it's easy to share.

To make the creation process better, let's also plan for a VS Code extension. It should provide a live preview panel right inside the editor, so a user can see their slide deck update in real-time as they type their Markdown. Let's build the whole ecosystem using TypeScript.