chore(sidebar): simplify navigation structure

src/components/app-sidebar.tsx

@@ -2,7 +2,6 @@
 
 import {
   AudioWaveform,
-  BookOpen,
   Bot,
   Command,
   Frame,
@@ -45,24 +44,10 @@ const data = {
   ],
   navMain: [
     {
-      title: "Playground",
-      url: "#",
+      title: "Problemset",
+      url: "/dashboard/problemset",
       icon: SquareTerminal,
       isActive: true,
-      items: [
-        {
-          title: "History",
-          url: "#",
-        },
-        {
-          title: "Starred",
-          url: "#",
-        },
-        {
-          title: "Settings",
-          url: "#",
-        },
-      ],
     },
     {
       title: "Models",
@@ -83,29 +68,6 @@ const data = {
         },
       ],
     },
-    {
-      title: "Documentation",
-      url: "#",
-      icon: BookOpen,
-      items: [
-        {
-          title: "Introduction",
-          url: "#",
-        },
-        {
-          title: "Get Started",
-          url: "#",
-        },
-        {
-          title: "Tutorials",
-          url: "#",
-        },
-        {
-          title: "Changelog",
-          url: "#",
-        },
-      ],
-    },
     {
       title: "Settings",
       url: "/dashboard/settings",