feat: daily timeline advanced UI and calendar integration

src/components/TopHeader.tsx

@@ -1,5 +1,5 @@
 import React, { useState } from 'react';
-import { LayoutTemplate, Menu, Home, Settings, Download, ZoomIn, ZoomOut, X, CalendarDays, Sparkles, Play } from 'lucide-react';
+import { LayoutTemplate, Menu, Home, Settings, Download, ZoomIn, ZoomOut, X, CalendarDays, Sparkles, Play, FolderOpen } from 'lucide-react';
 
 interface TopHeaderProps {
   currentStep: 'dashboard' | 'brand' | 'studio' | 'express' | 'content-grid' | 'template-builder' | 'production-form';
@@ -84,7 +84,7 @@ export const TopHeader: React.FC<TopHeaderProps> = ({
                 <button
                   className="w-full flex items-center gap-3 px-4 py-2.5 text-sm text-neutral-300 hover:bg-neutral-700 hover:text-white transition-colors"
                 >
-                  <Download size={14} /> Descargar
+                  <FolderOpen size={14} /> Abrir
                 </button>
               </div>
             </>
@@ -172,6 +172,17 @@ export const TopHeader: React.FC<TopHeaderProps> = ({
             Editor Pro 🎛️
           </button>
         )}
+        
+        {currentStep !== 'content-grid' && (
+          <button
+            onClick={() => setCurrentStep('content-grid')}
+            title="Abrir malla de contenidos"
+            className="flex items-center gap-1.5 px-3 py-1.5 rounded-lg bg-neutral-800 hover:bg-neutral-700 border border-neutral-700 text-white text-[10px] font-semibold transition-all"
+          >
+            <CalendarDays size={12} />
+            Malla de Contenidos
+          </button>
+        )}
 
         {isStudio && (
           <span className="text-[10px] font-medium text-neutral-500 uppercase tracking-wider">