feat(landing): rebuild as Next.js app with live product mocks

Replaces the static HTML page with a Next.js 15 + Tailwind v4 + Motion
app. The hero renders the dashboard itself - live tiles, ticking clock,
wandering metrics, pulsing status dots - instead of screenshots. Adds a
playable four-renderer switcher (bento/cards/index/console) with layout
animations, live monitor/domain/system mocks, and a cycling alert feed.

Vercel project dash is now git-connected with root dir landing/; pushes
deploy automatically. Canonical alias: dash-homelab.vercel.app.

Authored By: TDvorak <[email protected]>

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

landing/.gitignore

@@ -1,2 +1,4 @@
 .vercel
 .env*
+node_modules/
+.next/