feat(01-01): React + Vite + Tailwind v4 SPA scaffold con API client

- Vite react-ts project con base: '/postgenerator/' (Pitfall #9 risolto)
- Tailwind v4 via @tailwindcss/vite plugin + @import "tailwindcss" in index.css
- react-router-dom con BrowserRouter basename="/postgenerator"
- @tanstack/react-query con QueryClientProvider
- lucide-react installato per icone
- src/api/client.ts: API_BASE='/postgenerator/api', apiFetch<T> con error handling
- Dev proxy: /postgenerator/api -> http://localhost:8000 (strip /postgenerator)
- App.tsx: HomePage placeholder "Setup completo", struttura Routes pronta
- Build Vite: 253.90kB JS + 5.53kB CSS, nessun errore TypeScript

frontend/.gitignore

@@ -0,0 +1,24 @@
+# Logs
+logs
+*.log
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+pnpm-debug.log*
+lerna-debug.log*
+
+node_modules
+dist
+dist-ssr
+*.local
+
+# Editor directories and files
+.vscode/*
+!.vscode/extensions.json
+.idea
+.DS_Store
+*.suo
+*.ntvs*
+*.njsproj
+*.sln
+*.sw?