ui redesign, markdown fix + metadata and auth header

frontend/package.json

@@ -21,22 +21,30 @@
     "@codemirror/search": "^6.6.0",
     "@codemirror/state": "^6.6.0",
     "@codemirror/view": "^6.40.0",
+    "@fontsource-variable/inter": "^5.2.5",
+    "@fontsource-variable/jetbrains-mono": "^5.2.5",
     "@replit/codemirror-vim": "^6.3.0",
     "@tailwindcss/vite": "^4.2.2",
     "astro": "^6.0.8",
     "codemirror": "^6.0.2",
     "highlight.js": "^11.11.1",
+    "isomorphic-dompurify": "^2.18.0",
     "katex": "^0.16.44",
     "marked": "^17.0.5",
+    "marked-gfm-heading-id": "^4.1.2",
+    "marked-highlight": "^2.2.2",
+    "marked-katex-extension": "^5.1.5",
     "react": "^19.2.4",
     "react-dom": "^19.2.4",
     "tailwindcss": "^4.2.2",
     "zustand": "^5.0.12"
   },
   "devDependencies": {
+    "@astrojs/check": "^0.9.9",
     "@types/katex": "^0.16.8",
     "@types/node": "^25.5.0",
     "@types/react": "^19.2.14",
-    "@types/react-dom": "^19.2.3"
+    "@types/react-dom": "^19.2.3",
+    "typescript": "^5.9.3"
   }
 }