Add toast

frontend/package.json

@@ -21,10 +21,12 @@
   "devDependencies": {
     "bits-ui": "0.22.0",
     "clsx": "^2.1.1",
+    "mode-watcher": "^0.5.1",
     "prettier": "^3.5.3",
     "prettier-plugin-astro": "^0.14.1",
     "prettier-plugin-svelte": "^3.3.3",
     "prettier-plugin-tailwindcss": "^0.6.11",
+    "svelte-sonner": "^0.3.28",
     "tailwind-merge": "^3.0.2",
     "tailwind-variants": "^1.0.0",
     "tailwindcss-animate": "^1.0.7",