added mail service

lib/db.ts

@@ -0,0 +1,10 @@
+import { PrismaClient } from '@prisma/client'
+import * as process from 'process'
+
+declare global {
+  var prisma: PrismaClient | undefined
+}
+
+export const db = globalThis.prisma || new PrismaClient()
+
+if (process.env.NODE_ENV !== 'production') globalThis.prisma = db