feat(website): add layout with header, sidebar, footer and navigation

- Create Header component with logo, nav, theme toggle, language switcher
- Create Sidebar component with doc navigation from config
- Create Footer component
- Create MobileNav component with hamburger menu
- Create navigation config file (docsConfig)
- Integrate all layout components into [locale]/layout.tsx
- Add framer-motion for mobile nav animations
- All tests passing, build successful

website/package.json

@@ -13,6 +13,7 @@
   "dependencies": {
     "class-variance-authority": "^0.7.1",
     "clsx": "^2.1.1",
+    "framer-motion": "^12.29.0",
     "lucide-react": "^0.563.0",
     "next": "16.1.4",
     "next-intl": "^4.7.0",