jxnblk/mdx-deck ? reverse-engineered prompt

Build me a React based slide deck tool where I can write presentations in a markdown file and separate each slide with ---.

I want to be able to start a local dev server with one simple command, then move through the deck with the keyboard like a normal presentation. It should support MDX so I can mix markdown with React components, add speaker notes, and use a presenter view that shows the next slide and a timer. Please include a few built in themes so the deck can look different without much setup, and make it easy to add custom styling for individual slides or the whole deck.

It would be great if there were some helpful built in components like a header, footer, and notes area, plus a way to reveal content in steps on one slide. If you need to look up current MDX or styling docs online, feel free to do that.