chore(config): update vitest config, add vercel.json and manifest

- Update vitest.config.ts

- Add vercel.json for deployment configuration

- Add PWA manifest

vercel.json

@@ -0,0 +1,9 @@
+{
+  "$schema": "https://openapi.vercel.sh/vercel.json",
+  "crons": [
+    {
+      "path": "/api/cron/audit-cleanup",
+      "schedule": "0 3 * * *"
+    }
+  ]
+}