Add Prisma client initialization in markdown file

patterns/prisma-client.md

@@ -0,0 +1,9 @@
+import { PrismaClient } from '@prisma/client'
+
+const globalForPrisma = globalThis as unknown as { prisma: PrismaClient | undefined }
+
+export const prisma = globalForPrisma.prisma ?? new PrismaClient({
+  log: process.env.NODE_ENV === 'development' ? ['query', 'error', 'warn'] : ['error'],
+})
+
+if (process.env.NODE_ENV !== 'production') globalForPrisma.prisma = prisma