Remove cards stack, rack, trace, slab, relay, vault, unused preview
PNGs, and stack-only test scripts. Update home page, README, and Vite inputs.
Co-authored-by: Cursor <cursoragent@cursor.com>
L0–L7 folders stack on scroll with aligned max depth, labeled tabs that
stay consistent when L7 joins the rail, Cal embeds, preview screenshots,
Playwright tests, and updated README.
Co-authored-by: Cursor <cursoragent@cursor.com>
