chore: add config, prisma schema and client (Prisma 7 adapter)

src/lib/prisma.ts

@@ -0,0 +1,16 @@
+import 'dotenv/config'
+import { PrismaClient } from '@prisma/client'
+import { PrismaMariaDb } from '@prisma/adapter-mariadb'
+
+function createPrismaClient() {
+  const url = process.env.DATABASE_URL
+  if (!url) throw new Error('DATABASE_URL is not set')
+  const adapter = new PrismaMariaDb(url)
+  return new PrismaClient({ adapter })
+}
+
+const globalForPrisma = globalThis as unknown as { prisma: PrismaClient }
+
+export const prisma = globalForPrisma.prisma ?? createPrismaClient()
+
+if (process.env.NODE_ENV !== 'production') globalForPrisma.prisma = prisma