feat: fullscreen mode for all tabs + fix Dropbox/Supabase sync priority

src/components/HistoryView.tsx

@@ -1,5 +1,5 @@
 import React, { useState, useEffect } from 'react';
-import { History, RotateCcw, ChevronDown, ChevronRight, User, Calendar, Tag, Search, X, Edit2 } from 'lucide-react';
+import { History, RotateCcw, ChevronDown, ChevronRight, User, Calendar, Tag, Search, X, Edit2, Maximize2 } from 'lucide-react';
 import { getHistory, deleteHistoryEntry, HistoryEntry } from '../lib/supabase';
 import { ExcelRow } from '../types';
 import { useColumns } from '../contexts/ColumnsContext';
@@ -18,6 +18,7 @@ export function HistoryView({ headers, data, onRevert, onEdit }: HistoryViewProp
   const [loading, setLoading] = useState(true);
   const [expandedId, setExpandedId] = useState<string | null>(null);
   const [search, setSearch] = useState('');
+  const [isFullscreen, setIsFullscreen] = useState(false);
 
   useEffect(() => {
     loadHistory();
@@ -87,7 +88,15 @@ export function HistoryView({ headers, data, onRevert, onEdit }: HistoryViewProp
   }
 
   return (
-    <div className="space-y-6 animate-in fade-in slide-in-from-bottom-4 duration-500">
+    <div className={isFullscreen ? "fixed inset-0 z-40 bg-[#041021] p-6 overflow-auto" : "space-y-6 animate-in fade-in slide-in-from-bottom-4 duration-500"}>
+      {isFullscreen && (
+        <button
+          onClick={() => setIsFullscreen(false)}
+          className="fixed top-4 right-4 z-50 p-2 bg-slate-800 hover:bg-slate-700 text-slate-200 rounded-md transition-colors border border-slate-700"
+        >
+          <X className="w-5 h-5" />
+        </button>
+      )}
       <div className="flex items-center justify-between">
         <div>
           <h1 className="text-2xl font-bold text-white flex items-center gap-3">
@@ -122,6 +131,13 @@ export function HistoryView({ headers, data, onRevert, onEdit }: HistoryViewProp
             <RotateCcw className="w-4 h-4" />
             Refresh
           </button>
+          <button
+            onClick={() => setIsFullscreen(!isFullscreen)}
+            className="p-2 bg-slate-800 hover:bg-slate-700 text-slate-200 rounded-md transition-colors border border-slate-700"
+            title={isFullscreen ? "Exit fullscreen" : "Enter fullscreen"}
+          >
+            <Maximize2 className="w-5 h-5" />
+          </button>
         </div>
       </div>