Add /health to vercel API

web/pages/api/health.ts

@@ -0,0 +1,27 @@
+import type {NextApiRequest, NextApiResponse} from 'next'
+
+type HealthResponse = {
+  status: 'healthy' | 'unhealthy'
+  timestamp: string
+  version: string
+  uptime: number
+}
+
+export default function handler(req: NextApiRequest, res: NextApiResponse<HealthResponse>) {
+  res.setHeader('Access-Control-Allow-Origin', '*')
+  res.setHeader('Access-Control-Allow-Methods', 'GET, OPTIONS')
+  res.setHeader('Access-Control-Allow-Headers', 'Content-Type')
+
+  if (req.method === 'OPTIONS') {
+    res.status(200).end()
+    return
+  }
+
+  res.setHeader('Cache-Control', 'no-store')
+  res.status(200).json({
+    status: 'healthy',
+    timestamp: new Date().toISOString(),
+    version: process.env.NEXT_PUBLIC_APP_VERSION || 'unknown',
+    uptime: process.uptime(),
+  })
+}