feat: remove old archived email files from S3

[joybytes]

Summary

Added a daily task to remove archived template email files from S3. By default, it cleans a 1-day slice of files that are at least 14 days old. You can pass archived_from to backfill older files.

Testing

Without argument
Running the task without archived_from uses the default cleanup window:

• archived_to = now - 14 days (retention cutoff)
• archived_from = archived_to - 1 day So it only targets files archived in that 1-day window (between 15 and 14 days old), not all files older than 14 days.

docker exec -it notify-api-celery \
  celery -A run_celery.notify_celery call remove-archived-template-email-files-from-s3 \
  --queue=periodic-tasks

With argument
Providing archived_from widens/narrows the start of the window for backfill:

• lower bound becomes your provided archived_from
• upper bound is still archived_to = now - 14 days This means retention is still enforced + files newer than 14 days are never included.

docker exec -it notify-api-celery \
  celery -A run_celery.notify_celery call remove-archived-template-email-files-from-s3 \
  --queue=periodic-tasks \
  --kwargs='{"archived_after":"2026-04-17"}'

Ticket

Automatically remove stale email files from S3

[CrystalPea]

Hi, good work on this, well done!

I left some comments. This is not the full review yet - Github seems to be playing up and losing some of my comments, so I want to submit to see what came through and avoid repeating myself. I will finish the review in a second swipe now.

[CrystalPea]

I reviewed the rest of the PR and I have no more comments 🙌🏼

[joybytes]

@CrystalPea could you give a final look to the implementation of dao_get_archived_template_email_files_older_than please? 🙏

I did some refactoring, and I am now using older_than and .scalar()

I noticed that the other keyset/cursor functions in our repo seems to use this pattern, so I tried to follow the same
(eg.dao_get_paginated_inbound_sms_for_service_for_public_api, get_notifications_for_service)

I also decided to use PAGE_SIZE config variables, which is what inbound notifications seem to use, so I just decided to follow the same limit for sizing