Feature mail scheduler

[Loulou5702]

This new feature allows the scheduler to plan and send newsletters as needed, according to a defined periodicity.

For now, the script executed when sending emails is a simple "hello world" in the console to avoid consuming emails in Postmark. However, you can replace it with the actual newsletter-sending script that we have already developed.

The script checks every 10 seconds if there are newsletters to send. If so, it executes the specified script (currently "hello.ts" for testing purposes).

After sending an email, it schedules the next one based on the user's chosen periodicity.

In this example, we plan to send two newsletters at 19:10.
One person wants another newsletter in 5 minutes, and the other in 6 minutes (this demonstrates different periodicity management).

Example in the terminal :

Looking at the database after execution :

[adguernier]

thought: Smart approach but we usually use cron jobs to run this kind of script: cron is designed for this and is more efficient. You can search on the internet for setInterval vs cron to make your own opinion.
To do thah you can set up node-cron for instance https://www.digitalocean.com/community/tutorials/nodejs-cron-jobs-by-examples