add feature to send an email reminder to RSVPs that their event is in 24 hours & update their RSVP if it's changed

[vs77bb]

Discussed in #259

^{Originally posted by aliyakernel May 23, 2024}
it would be helpful for convo to auto-send email reminders to the RSVPs of a convo event 24 hours in advance reminding them they are RSVPed to convo event (link the convo event link) & to read the description to be well prepared for it and update their calendar response if they can no longer attend.

i can create draft copy! i will work on it and DM Angela

[vs77bb]

Reminder email going to all Convo RSVPs 24 hour before the Convo event begins

Subject Line: [Kernel] Reminder: You’re Attending [Enter Convo Name Here] in 24 Hours!

Hello [Enter Name or Email Here],

I’m Hedwig the Kernel Owl here to remind you about the Convo event you RSVPed to, [Enter Convo Name Here], starting in 24 hours on [Enter date at time here].

If anything has changed on your end—and we get it, life happens—we ask you to update your RSVP so the organizer has a good understanding who they can expect at the event!

Otherwise, we’re looking forward to seeing you in 24 hours 🦉.

Tweet Tweet,

Hedwig

[probablyangg]

smol Spec

• only recipients in the database receive a reminder emails (24 hr, 1 hr and 1min)
• when user RSVPs, schedule the email reminders for them, save the email IDs in the database
• when a user cancels their RSVP, fetch id from the database, cancel their scheduled email

[probablyangg]

Haven't been able to test the cron job, not sureeee what's going wrong, will get back to it soon