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)/documentos/page.tsx

@@ -379,11 +379,11 @@ function DeclaracionesTab() {
         <div className="flex flex-wrap items-end gap-3 mb-4 pb-3 border-b">
           <div className="flex items-center gap-2">
             <label className="text-xs text-muted-foreground">Desde</label>
-            <Input type="date" value={fechaDesde} onChange={(e) => setFechaDesde(e.target.value)} className="h-8 w-[150px] text-sm" />
+            <Input type="date" value={fechaDesde} onChange={(e) => setFechaDesde(e.target.value)} className="h-8 w-full sm:w-[150px] text-sm" />
           </div>
           <div className="flex items-center gap-2">
             <label className="text-xs text-muted-foreground">Hasta</label>
-            <Input type="date" value={fechaHasta} onChange={(e) => setFechaHasta(e.target.value)} className="h-8 w-[150px] text-sm" />
+            <Input type="date" value={fechaHasta} onChange={(e) => setFechaHasta(e.target.value)} className="h-8 w-full sm:w-[150px] text-sm" />
           </div>
         </div>
 
@@ -552,7 +552,7 @@ function UploadDialog({ onClose }: { onClose: () => void }) {
 
   return (
     <Dialog open onOpenChange={(o) => { if (!o) onClose(); }}>
-      <DialogContent className="max-w-2xl max-h-[90vh] overflow-y-auto">
+      <DialogContent className="max-w-[95vw] md:max-w-2xl max-h-[90vh] overflow-y-auto">
         <DialogHeader>
           <DialogTitle>Subir declaración</DialogTitle>
           <DialogDescription>