feat: add admin dashboard with sidebar navigation and stats overview

Replace placeholder panel with a full dashboard landing page showing
bot stats, leaderboards, and recent events from /api/stats. Add
sidebar navigation with placeholder pages for Users, Items, Classes,
Quests, Lootdrops, Moderation, Transactions, and Settings. Update
theme to match Aurora design guidelines.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

panel/package.json

@@ -9,19 +9,22 @@
     "preview": "vite preview"
   },
   "dependencies": {
+    "class-variance-authority": "^0.7.1",
+    "clsx": "^2.1.1",
+    "lucide-react": "^0.564.0",
     "react": "^19.1.0",
     "react-dom": "^19.1.0",
-    "react-router-dom": "^7.6.1"
+    "tailwind-merge": "^3.4.0",
+    "tailwindcss-animate": "^1.0.7"
   },
   "devDependencies": {
+    "@tailwindcss/vite": "^4.1.10",
     "@types/react": "^19.1.6",
     "@types/react-dom": "^19.1.6",
     "@vitejs/plugin-react": "^4.6.0",
     "autoprefixer": "^10.4.21",
-    "daisyui": "^5.0.43",
     "postcss": "^8.5.6",
     "tailwindcss": "^4.1.10",
-    "@tailwindcss/vite": "^4.1.10",
     "typescript": "^5.9.3",
     "vite": "^6.3.5"
   }