feat: one gateway port with path-mounted frontends, markdown chat, collapsible sidebars

ui/package.json

@@ -13,6 +13,10 @@
     "prepare": "svelte-kit sync || echo ''",
     "preview": "vite preview"
   },
+  "dependencies": {
+    "dompurify": "^3.4.14",
+    "marked": "^18.0.11"
+  },
   "devDependencies": {
     "@biomejs/biome": "2.5.9",
     "@fontsource-variable/inter": "^5.3.0",