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/tsconfig.app.json

@@ -0,0 +1,28 @@
+{
+  "compilerOptions": {
+    "tsBuildInfoFile": "./node_modules/.tmp/tsconfig.app.tsbuildinfo",
+    "target": "ES2022",
+    "useDefineForClassFields": true,
+    "lib": ["ES2022", "DOM", "DOM.Iterable"],
+    "module": "ESNext",
+    "types": ["vite/client"],
+    "skipLibCheck": true,
+
+    /* Bundler mode */
+    "moduleResolution": "bundler",
+    "allowImportingTsExtensions": true,
+    "verbatimModuleSyntax": true,
+    "moduleDetection": "force",
+    "noEmit": true,
+    "jsx": "react-jsx",
+
+    /* Linting */
+    "strict": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "erasableSyntaxOnly": true,
+    "noFallthroughCasesInSwitch": true,
+    "noUncheckedSideEffectImports": true
+  },
+  "include": ["src"]
+}