feat(view): show default artboard canvas

view/App.tsx

@@ -12,7 +12,7 @@ export function App({ app }: AppProps) {
   const zoomPercent = Math.round(state.editor.viewport.zoom * 100);
 
   return (
-    <main className="flex min-h-screen flex-col bg-background text-foreground">
+    <main className="flex h-full flex-col bg-background text-foreground">
       <header className="flex h-12 items-center justify-between border-b px-4">
         <h1 className="font-semibold">Image Studio</h1>
         <div className="text-sm text-muted-foreground">