fix(layout): wrap children in a flex-1 div for consistent layout behavior

src/app/(app)/playground/@workspace/@editor/layout.tsx

@@ -11,7 +11,9 @@ export default function WorkspaceEditorLayout({
   return (
     <div className="h-full flex flex-col">
       <WorkspaceEditorHeader />
+      <div className="flex-1">
         {children}
+      </div>
       <WorkspaceEditorFooter />
     </div>
   );