✨ feat(order): add customer email and optional fields, update order creation flow

- Added `customerEmail` field to Order model.
- Made `customerNote` optional in the Order model.
- Updated order creation logic to send a tracking email.
- Updated order validation to handle optional fields.
- Refactored configurations import path from `errors/configs` to `configs`.
- Minor modifications across account and order services for consistency.

src/app/utils/mail_sender.ts

@@ -1,5 +1,5 @@
 import nodemailer from 'nodemailer';
-import { configs } from '../errors/configs';
+import { configs } from '../configs';
 type TMailContent = {
   to: string,
   subject: string,