feat: integrate Prisma for database management

src/prisma/prisma.service.ts

@@ -0,0 +1,9 @@
+import { Injectable, OnModuleInit } from '@nestjs/common';
+import { PrismaClient } from 'generated/prisma/client';
+
+@Injectable()
+export class PrismaService extends PrismaClient implements OnModuleInit {
+  async onModuleInit() {
+    await this.$connect();
+  }
+}