feat: add download as markdown button to bookmark cards

[davidorban]

Summary

Adds a FileText button (visible on hover, left of the existing media download button) that exports any bookmark as a .md file with a single click.

What's exported

# Tweet by @handle

**Author:** Name (@handle)
**Date:** Mar 15, 2026
**URL:** https://twitter.com/handle/status/...
**Categories:** AI & Machine Learning, Dev Tools

---

Full tweet text here (URLs preserved so truncated threads
show their continuation link)

> *This tweet may be part of a longer thread. [Read on X ↗](...)*

---

![Image](https://pbs.twimg.com/media/...)

Design decisions

• Entirely client-side — no new API routes, no new dependencies, no backend changes
• URLs preserved — unlike the card display which strips t.co links, the export keeps them so truncated threads include the continuation link
• Thread hint — when the text ends with a t.co URL (sign of a truncated thread), a blockquote note is appended with a direct link to X
• Photo media embedded as ![Image](url) for inline display in any Markdown viewer; videos/GIFs become links back to the tweet
• Named tweet-{tweetId}.md for easy identification

Changes

• components/bookmark-card.tsx — adds FileText import, handleDownloadMarkdown() function, and the hover button (1 file, +62 lines)

Checklist

• Tested locally
• npx tsc --noEmit passes
• No new warnings
• No new dependencies
• No new API routes or backend changes