feat: Convert all app files to JS

packages/backend/src/apps/smtp/common/transporter.js

@@ -0,0 +1,15 @@
+import nodemailer from 'nodemailer';
+
+const transporter = ($) => {
+  return nodemailer.createTransport({
+    host: $.auth.data.host,
+    port: $.auth.data.port,
+    secure: $.auth.data.useTls,
+    auth: {
+      user: $.auth.data.username,
+      pass: $.auth.data.password,
+    },
+  });
+};
+
+export default transporter;