Fix sidebar session list responsiveness

frontend/app/app/assistant.tsx

@@ -14,7 +14,11 @@ import {
 } from "@/components/assistant-ui/activity-panel";
 import { Thread } from "@/components/assistant-ui/thread";
 import { ThreadListSidebar } from "@/components/assistant-ui/threadlist-sidebar";
-import { SidebarInset, SidebarProvider } from "@/components/ui/sidebar";
+import {
+	SidebarInset,
+	SidebarProvider,
+	SidebarTrigger,
+} from "@/components/ui/sidebar";
 import { ClawSessionReplayProvider } from "@/lib/claw-session-replay";
 import { ClawAccountGate, useClawAccount } from "./claw-account-gate";
 
@@ -85,6 +89,7 @@ export const Assistant = () => {
 				<ActivityProvider>
 					<SidebarProvider>
 						<div className="flex h-dvh w-full">
+							<SidebarTrigger className="fixed top-3 left-3 z-40 size-9 rounded-lg bg-background/90 shadow-sm ring-1 ring-border backdrop-blur sm:hidden" />
 							<ThreadListSidebar
 								account={account}
 								onLogout={() => setAccount(null)}