Feature/single time msg conf

[ArthurErlich]

Sending E-Mail Notification Once

Addition for the frosh:monitor Command

This addition introduces a configuration feature to send an E-Mail notification only once within a specified time frame. The goal is to reduce spam by preventing repeated notifications when a mail has already been sent.

There are two settings:

• Enable the option
• Specify the time interval for the next E-Mail (TTL of the cache)
  

To implement this, I moved the email-sending functionality to its own method to keep the code clean and maintainable.

Persistent E-Mail Sent Flag

To track when an E-Mail has been sent, I use the cache instead of the database. This approach avoids writing to the database or creating a migration if changes are needed later.

The cache is a suitable solution because we can simply check if the cache is set. If it isn't, the notification mail is sent and the cache key added.

I hope the use of the cache is acceptable in this context.