feat(frontend): add database management surface

frontend/src/shell/ModelActivityPanel.tsx

@@ -62,10 +62,12 @@ export function ModelActivityPanel({
   desktopSplit = false,
   onClose,
   onOpenWorkspaceManager,
+  hidden = false,
 }: {
   desktopSplit?: boolean;
   onClose: () => void;
   onOpenWorkspaceManager?: () => void;
+  hidden?: boolean;
 }) {
   const activityLog = useSessionStore((s) => s.activityLog);
   const visibleActivity = activityLog.filter(isVisibleModelActivity);
@@ -80,7 +82,7 @@ export function ModelActivityPanel({
   }, [visibleCount, visibleTail]);
 
   return (
-    <aside className={desktopSplit
+    <aside aria-hidden={hidden || undefined} hidden={hidden} className={desktopSplit
       ? "static z-auto flex min-w-0 w-[var(--activity-panel-width)] shrink-0 flex-col border-r-0 bg-sidebar"
       : "fixed inset-y-0 left-0 z-30 flex min-w-0 w-[min(90vw,24rem)] shrink-0 flex-col border-r border-border bg-sidebar"
     }>