Add GAIA website

[kovtcharov]

Summary

Astro + Tailwind landing page for amd-gaia.ai serving two audiences:

End users — Download the desktop Agent UI installer, see what GAIA can do
Developers — Explore the Python SDK and C++ framework, build custom agents

Key Pages

• Landing page — Hero, feature highlights, download buttons, SDK code examples
• Download page — Platform-specific installers with OS detection, links to R2-hosted builds
• Python SDK overview — Agent creation, tool decorator, RAG, Chat SDK with interactive code examples
• C++ Framework overview — C++ agent development, LemonadeClient, background monitoring
• Documentation links — Points to amd-gaia.ai/docs (Mintlify) for full SDK reference and guides

Technical

• Astro + Tailwind static site
• Configured for Railway or Cloudflare Pages deployment
• Interactive code examples with typewriter animation
• OS-specific install commands and download buttons (Windows/Linux/macOS)
• Auto-label CI for website/ changes

Test plan

• cd website && npm install && npm run build succeeds
• npx serve dist -s serves the site locally
• Download buttons link to correct R2 URLs per platform
• Python SDK code examples are accurate and match current API
• C++ framework code examples are accurate
• All doc links point to amd-gaia.ai
• Deployment builds and serves correctly

[kovtcharov]

Closing — the goal of this PR (a public website at amd-gaia.ai) has been achieved via the Mintlify docs site instead of a separate Astro+Tailwind landing page.

Current state:

• `https://amd-gaia.ai/\` → 308 redirect to `/docs` (Mintlify) ✅
• `docs/docs.json` defines the live navigation: Documentation, C++ Framework, Python Framework, SDK Reference, Reference, Deployment, Integrations, Plans
• Page metadata in `docs.json` already covers the audiences this PR was targeting (end users via the Quickstart + setup guides; developers via the SDK / C++ Framework tabs)

Why not rebase:

• Branch is ~700 files behind `main` (last update was March 6); the Astro site would conflict heavily with the doc/repo changes that have landed since
• Maintaining two parallel website systems (Astro + Mintlify) doubles the surface area for drift between landing copy and SDK reality
• The "What we ship for v0.17.3 → website launch" milestone item is effectively delivered by the live Mintlify site

If we later want a richer marketing landing page on top of the docs, it should be a fresh PR built against current `main` rather than reviving this one.

[kovtcharov]

Reopened — to be revisited in a future milestone. Branch is significantly out of date relative to main and the Mintlify docs at amd-gaia.ai already cover the current website needs, but keeping this open as a parking spot for the richer marketing landing page idea. Will rebase or rebuild against current main when picked up.

[kovtcharov]

Rebased onto current main (was ~700 files / ~6 weeks behind). Branch now has a single clean commit on top of main:

• Adds website/ (Astro + Tailwind landing site, unchanged from prior commits)
• Adds website: rule to .github/labeler.yml so future website-only PRs auto-tag

Skipped the unrelated "Agent SDK changes" → "Chat SDK changes" comment edit from the old branch since main has since reverted to "Agent SDK changes" naming. PR is now MERGEABLE and CI is running fresh.