feat: Re-compute the given items cost job.

feat: Optimize the architecture.

server/src/loaders/mongoose.ts

@@ -0,0 +1,11 @@
+import mongoose from 'mongoose';
+import { Db } from 'mongodb';
+import config from '@/../config/config';
+
+export default async (): Promise<Db> => {
+  const connection = await mongoose.connect(
+    config.mongoDb.databaseURL,
+    { useNewUrlParser: true, useCreateIndex: true },
+  );
+  return connection.connection.db;
+};