feat(01-05): add protected dashboard layout and page

- Create UserNav component with logout functionality
- Add dashboard layout with header, navigation, and user info
- Create dashboard page displaying plan info and onboarding steps
- All text in Italian for target audience

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/app/(dashboard)/dashboard/page.tsx

@@ -0,0 +1,113 @@
+import { createClient } from '@/lib/supabase/server'
+import { redirect } from 'next/navigation'
+import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card'
+
+export default async function DashboardPage() {
+  const supabase = await createClient()
+
+  const { data: { user } } = await supabase.auth.getUser()
+
+  if (!user) {
+    redirect('/login')
+  }
+
+  // Get profile with plan details
+  const { data: profile } = await supabase
+    .from('profiles')
+    .select(`
+      *,
+      plans (
+        name,
+        display_name_it,
+        features
+      )
+    `)
+    .eq('id', user.id)
+    .single()
+
+  const features = profile?.plans?.features as {
+    posts_per_month?: number
+    ai_models?: string[]
+    social_accounts?: number
+  } | null
+
+  return (
+    <div className="space-y-6">
+      <div>
+        <h1 className="text-2xl font-bold text-gray-900">Dashboard</h1>
+        <p className="text-gray-500">Benvenuto in Leopost</p>
+      </div>
+
+      <div className="grid grid-cols-1 md:grid-cols-3 gap-6">
+        <Card>
+          <CardHeader>
+            <CardTitle className="text-lg">Il tuo piano</CardTitle>
+            <CardDescription>
+              {profile?.plans?.display_name_it || 'Gratuito'}
+            </CardDescription>
+          </CardHeader>
+          <CardContent>
+            <ul className="space-y-2 text-sm text-gray-600">
+              <li>
+                <span className="font-medium">{features?.posts_per_month || 10}</span> post/mese
+              </li>
+              <li>
+                <span className="font-medium">{features?.social_accounts || 1}</span> account social
+              </li>
+              <li>
+                <span className="font-medium">{features?.ai_models?.length || 1}</span> modelli AI
+              </li>
+            </ul>
+          </CardContent>
+        </Card>
+
+        <Card>
+          <CardHeader>
+            <CardTitle className="text-lg">Prossimi passi</CardTitle>
+            <CardDescription>
+              Completa la configurazione
+            </CardDescription>
+          </CardHeader>
+          <CardContent>
+            <ul className="space-y-2 text-sm">
+              <li className="flex items-center gap-2">
+                <span className="w-5 h-5 rounded-full bg-green-100 text-green-600 flex items-center justify-center text-xs">
+                  ✓
+                </span>
+                Account creato
+              </li>
+              <li className="flex items-center gap-2 text-gray-400">
+                <span className="w-5 h-5 rounded-full bg-gray-100 flex items-center justify-center text-xs">
+                  2
+                </span>
+                Collega social (Phase 2)
+              </li>
+              <li className="flex items-center gap-2 text-gray-400">
+                <span className="w-5 h-5 rounded-full bg-gray-100 flex items-center justify-center text-xs">
+                  3
+                </span>
+                Configura brand (Phase 3)
+              </li>
+            </ul>
+          </CardContent>
+        </Card>
+
+        <Card>
+          <CardHeader>
+            <CardTitle className="text-lg">Attivita</CardTitle>
+            <CardDescription>
+              Le tue statistiche
+            </CardDescription>
+          </CardHeader>
+          <CardContent>
+            <div className="text-center py-4 text-gray-400 text-sm">
+              Nessuna attivita ancora.
+              <br />
+              Inizia collegando un account social!
+            </div>
+          </CardContent>
+        </Card>
+      </div>
+    </div>
+  )
+}