skalara-core/app/w/[workspaceID]/layout.tsx

import { WorkspaceSelector } from "@/components/workspace-selector";
export default function WorkspaceLayout({
  children,
  params: { workspaceID },
}: {
  children: React.ReactNode;
  params: { workspaceID: string };
}) {
  return (
    <div className="flex flex-row">
      <WorkspaceSelector workspaceID={workspaceID} />
      {children}
    </div>
  );
}