Send automated failed payment emails

[domdomegg]

When a recurring payment fails, we send an alert to an internal Slack channel for us to follow-up with the donor.

This is manual and time consuming. While it was fine last year, our growth has meant more donors and more failing recurring payments this year - and therefore more time taken to follow-up with all of them.

Instead, I think we should:

• Send the donor an email that tells them their card has been declined, and the reason for it
• Content should include:
  • Letting them know we'll automatically retry
  • A link for them to change their card details
  • A link to cancel recurring donations

Some questions to figure out beforehand:

• What should we do if Stripe Radar has blocked it potential fraud? (maybe just alert Slack channel for now still?)
• How can we actually update card details securely? I would think we'd need to take them to some page on the platform with a token in the URL, which authenticates them and shows them some Stripe elements fields that can replace the card on the Stripe customer and update the payment method on the donation. Basically, an automated way of doing 'Changing a recurring donor’s card details' from the 'Using the Raise platform' doc.
• For cancelling recurring donation, probably can take similar approach. Might be rare enough that we can just have this be 'contact us to cancel' for now.