Add vercel.json for default React vite.js template (#755)

Fixes #741 
See: https://vercel.com/docs/project-configuration#rewrites-examples

e2e-tests/snapshots/engine.spec.ts_send-message-to-engine-1.txt

@@ -401,6 +401,11 @@
           "content": "// File contents excluded from context",
           "force": false
         },
+        {
+          "path": "vercel.json",
+          "content": "{\n  \"$schema\": \"https://openapi.vercel.sh/vercel.json\",\n  \"rewrites\": [\n    {\n      \"source\": \"/(.*)\",\n      \"destination\": \"/index.html\"\n    }\n  ]\n}\n",
+          "force": false
+        },
         {
           "path": "vite.config.ts",
           "content": "import { defineConfig } from \"vite\";\nimport dyadComponentTagger from \"@dyad-sh/react-vite-component-tagger\";\nimport react from \"@vitejs/plugin-react-swc\";\nimport path from \"path\";\n\nexport default defineConfig(() => ({\n  server: {\n    host: \"::\",\n    port: 8080,\n  },\n  plugins: [dyadComponentTagger(), react()],\n  resolve: {\n    alias: {\n      \"@\": path.resolve(__dirname, \"./src\"),\n    },\n  },\n}));\n",