Auto-generate project listing from GitHub API

## Summary
The project links table in the landing page is manually maintained and could get stale as new repos are added.

## Tasks
- [ ] Fetch repo list from GitHub API on page load (or at build time)
- [ ] Auto-categorize repos (web apps, macOS apps, npm packages, CLI tools)
- [ ] Add search/filter for the project listing
- [ ] Add live status badges (last commit, CI status)