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

src/components/ProductDescriptions.tsx

@@ -223,7 +223,16 @@ export function ProductDescriptions({ data, headers, asinColumnIndex, onEdit, ro
   ];
 
   return (
-    <div className="flex flex-col h-full">
+    <div className={isFullscreen ? "fixed inset-0 z-40 bg-[#041021] p-6 overflow-auto" : "flex flex-col h-full"}>
+      {isFullscreen && (
+        <button
+          onClick={() => setIsFullscreen(false)}
+          className="fixed top-4 right-4 z-50 w-10 h-10 flex items-center justify-center bg-slate-800/90 backdrop-blur border border-slate-600 text-white rounded hover:bg-slate-700 hover:scale-105 transition-all"
+          title="Exit fullscreen"
+        >
+          <X className="w-5 h-5" />
+        </button>
+      )}
       <div className="flex flex-wrap gap-2 mb-6">
         {tabs.map(tab => (
           <button
@@ -239,6 +248,13 @@ export function ProductDescriptions({ data, headers, asinColumnIndex, onEdit, ro
             {tab.label}
           </button>
         ))}
+        <button
+          onClick={() => setIsFullscreen(true)}
+          className="ml-auto p-2 text-slate-400 hover:text-white hover:bg-slate-700 rounded transition-colors"
+          title="Fullscreen"
+        >
+          <Maximize2 className="w-5 h-5" />
+        </button>
       </div>
 
       <div className="flex flex-wrap gap-4 mb-6 bg-slate-800 p-4 rounded-xl border border-slate-700 shadow-sm">