feat: RRSS hub estilo Miia + Ad Tracker por cliente

Replica agua-miia/rrss (hub, archivo, octubre 2026 con 27 piezas) y añade Ad Tracker por tenant al estilo Brava (periodos, Meta+Google, CPL/clics, campañas).

Co-authored-by: Cursor <cursoragent@cursor.com>

src/app/dashboard/layout.tsx

@@ -10,7 +10,8 @@ import {
   LogOut,
   UserCheck,
   CalendarDays,
-  Radio
+  Radio,
+  Megaphone
 } from 'lucide-react';
 import { createClient } from '@/lib/supabase/server';
 import { logoutAction } from '@/app/auth/actions';
@@ -77,6 +78,13 @@ export default async function DashboardLayout({
               <CalendarDays className="w-4 h-4 text-pink-400" />
               Calendario Editorial
             </Link>
+            <Link
+              href="/dashboard/ad-tracker"
+              className="flex items-center gap-3 px-3 py-2.5 rounded-lg text-sm font-medium text-gray-300 hover:text-white hover:bg-gray-800/60 transition-all"
+            >
+              <Megaphone className="w-4 h-4 text-violet-400" />
+              Ad Tracker
+            </Link>
             <Link
               href="/dashboard/activos"
               className="flex items-center gap-3 px-3 py-2.5 rounded-lg text-sm font-medium text-gray-300 hover:text-white hover:bg-gray-800/60 transition-all"