fix: Vercel production readiness for React SPA (vercel.json, .nvmrc, engines)

.nvmrc

@@ -0,0 +1 @@
+20

README.md

@@ -31,6 +31,7 @@ Interact is an enterprise-grade employee engagement platform that transforms wor
 - [Overview](#overview)
 - [Documentation](#-documentation)
 - [Quick Start](#-quick-start)
+- [Deploying to Vercel](#-deploying-to-vercel)
 - [Project Structure](#️-project-structure)
 - [Current Features](#-current-features)
 - [Roadmap Highlights](#-roadmap-highlights)
@@ -79,6 +80,53 @@ Interact is an enterprise-grade employee engagement platform that transforms wor
 - **[.github/base44-updates.md](./.github/base44-updates.md)** - Base44 visual canvas integration guide and module architecture
 - **[.github/agents.md](./.github/agents.md)** - AI agent context log and historical development decisions
 
+## 🚀 Deploying to Vercel
+
+**Project type:** Vercel Web App — React SPA (single-page application) built with Vite.
+
+### One-click deploy
+
+[![Deploy with Vercel](https://vercel.com/button)](https://vercel.com/new/clone?repository-url=https://github.com/Krosebrook/interact)
+
+### Manual deploy
+
+1. Import the repository at [vercel.com/new](https://vercel.com/new).
+2. Vercel auto-detects the Vite framework. Confirm the settings:
+   - **Framework Preset:** Vite
+   - **Build Command:** `npm run build`
+   - **Output Directory:** `dist`
+   - **Install Command:** `npm ci`
+   - **Node.js Version:** 20
+3. Add the required environment variables (see below), then click **Deploy**.
+
+### Environment variables
+
+Copy `.env.example` to understand all available variables. The following are **required** for the app to function:
+
+| Variable | Description |
+|---|---|
+| `VITE_BASE44_APP_ID` | Your Base44 application ID |
+| `VITE_BASE44_BACKEND_URL` | Base44 backend server URL (e.g. `https://your-backend.base44.app`) |
+
+The following are **optional** but enable specific features:
+
+| Variable | Description |
+|---|---|
+| `VITE_BASE44_API_URL` | Base44 API URL (if different from backend URL) |
+| `VITE_COMPANY_ID` | Company identifier |
+| `VITE_ENABLE_ANALYTICS` | Enable analytics (`true`/`false`) |
+| `VITE_GOOGLE_ANALYTICS_ID` | Google Analytics measurement ID |
+| `VITE_STRIPE_PUBLISHABLE_KEY` | Stripe publishable key (payments feature) |
+
+Set these in the Vercel dashboard under **Settings → Environment Variables**, or via the Vercel CLI:
+
+```bash
+vercel env add VITE_BASE44_APP_ID
+vercel env add VITE_BASE44_BACKEND_URL
+```
+
+> **Note:** All `VITE_` prefixed variables are bundled into the client-side build. Never put secrets in `VITE_` variables. Backend/serverless function secrets (OpenAI keys, Stripe secret keys, etc.) should be set separately in your Base44 dashboard.
+
 ## 🚀 Quick Start
 
 ### Prerequisites

package.json

@@ -3,6 +3,10 @@
   "private": true,
   "version": "0.0.0",
   "type": "module",
+  "engines": {
+    "node": ">=20",
+    "npm": ">=10"
+  },
   "scripts": {
     "dev": "vite",
     "build": "vite build",

vercel.json

@@ -5,15 +5,6 @@
   "outputDirectory": "dist",
   "installCommand": "npm ci",
   "devCommand": "npm run dev",
-  "env": {
-    "NODE_VERSION": "20"
-  },
-  "build": {
-    "env": {
-      "VITE_API_URL": "@api_url",
-      "VITE_BASE44_PROJECT_ID": "@base44_project_id"
-    }
-  },
   "regions": ["iad1"],
   "headers": [
     {
@@ -44,15 +35,8 @@
   ],
   "rewrites": [
     {
-      "source": "/api/:path*",
-      "destination": "/api/:path*"
-    }
-  ],
-  "redirects": [
-    {
-      "source": "/login",
-      "destination": "/auth/login",
-      "permanent": false
+      "source": "/(.*)",
+      "destination": "/index.html"
     }
   ],
   "cleanUrls": true,