feat(ui): make dashboard responsive for iPhone and mobile devices

- Add Sheet primitive component for mobile drawers
- Add MobileNav with hamburger menu for dashboard layout
- Hide desktop sidebars on mobile; show mobile header
- Make dashboard header responsive with stacked layout on small screens
- Hide selector text on mobile, show icons only
- Convert fixed-width filters to responsive widths (CFDI, Clientes, Admin, Documentos, Alertas)
- Cap dialog widths to 95vw on mobile (CFDI viewer, Documentos, Reportes, Contribuyentes, Facturación)
- Make calendar grid smaller and use single-letter weekdays on mobile
- Update viewport to include viewport-fit=cover for Samsung safe areas

apps/web/app/(dashboard)/facturacion/page.tsx

@@ -812,7 +812,7 @@ export default function FacturacionPage() {
       {/* Modal de búsqueda de conceptos previos */}
       {showConceptoSearch && (
         <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50">
-          <div className="bg-white dark:bg-zinc-900 rounded-xl shadow-2xl w-full max-w-3xl max-h-[80vh] flex flex-col m-4">
+          <div className="bg-white dark:bg-zinc-900 rounded-xl shadow-2xl w-full max-w-[95vw] md:max-w-3xl max-h-[80vh] flex flex-col m-4">
             <div className="flex items-center justify-between p-4 border-b">
               <h3 className="text-lg font-semibold">Buscar Concepto en Facturas</h3>
               <Button variant="ghost" size="icon" onClick={() => setShowConceptoSearch(false)}>