feat(01-04): layout, routing, API hooks, tipi TypeScript, Dashboard, Settings

- types.ts: CalendarSlot, GeneratedPost, PostResult, JobStatus, Settings, SettingsStatus
- api/client.ts: aggiunto apiGet, apiPost, apiPut, apiDownload, triggerDownload
- api/hooks.ts: 10+ hooks TanStack Query (settings, generate, job polling, CSV export)
- components/Layout.tsx + Sidebar.tsx: sidebar stone/amber palette con 4 nav link
- pages/Dashboard.tsx: banner API key, quick actions link, step guide
- pages/Settings.tsx: form completo (API key password, LLM select, brand, nicchie checkbox)
- App.tsx: 5 route con BrowserRouter basename='/postgenerator', QueryClientProvider, Layout

frontend/src/App.tsx

@@ -1,5 +1,11 @@
 import { QueryClient, QueryClientProvider } from '@tanstack/react-query'
 import { BrowserRouter, Route, Routes } from 'react-router-dom'
+import { Layout } from './components/Layout'
+import { Dashboard } from './pages/Dashboard'
+import { GenerateCalendar } from './pages/GenerateCalendar'
+import { GenerateSingle } from './pages/GenerateSingle'
+import { OutputReview } from './pages/OutputReview'
+import { Settings } from './pages/Settings'
 
 const queryClient = new QueryClient({
   defaultOptions: {
@@ -10,25 +16,20 @@ const queryClient = new QueryClient({
   },
 })
 
-function HomePage() {
-  return (
-    <div className="min-h-screen bg-gray-950 text-gray-100 flex items-center justify-center">
-      <div className="text-center space-y-4">
-        <h1 className="text-4xl font-bold tracking-tight">PostGenerator</h1>
-        <p className="text-gray-400 text-lg">Setup completo — pronto per la business logic.</p>
-      </div>
-    </div>
-  )
-}
-
 function App() {
   return (
     <QueryClientProvider client={queryClient}>
       {/* basename must match the nginx subpath and Vite base config */}
       <BrowserRouter basename="/postgenerator">
-        <Routes>
-          <Route path="/" element={<HomePage />} />
-        </Routes>
+        <Layout>
+          <Routes>
+            <Route path="/" element={<Dashboard />} />
+            <Route path="/genera" element={<GenerateCalendar />} />
+            <Route path="/genera-singolo" element={<GenerateSingle />} />
+            <Route path="/risultati/:jobId" element={<OutputReview />} />
+            <Route path="/impostazioni" element={<Settings />} />
+          </Routes>
+        </Layout>
       </BrowserRouter>
     </QueryClientProvider>
   )