fix(files_reminders): keep batch alive on per-row failure

[solracsf]

Summary

The job iterates overdue reminders ordered by due_date ASC and only caught DoesNotExistException. A UserNotFoundException (thrown by ReminderService::send when the recipient user record is missing, e.g.: an orphaned LDAP user that was removed without firing UserDeletedEvent) or any other Throwable escaped the foreach, terminating the whole batch.

Because findOverdue re-pulls the same oldest row on every cron tick, this stalled the entire reminder pipeline indefinitely.

Catch Throwable, log at error level, and continue to the next reminder.

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)
• Labels added where applicable (ex: bug/enhancement, 3. to review, feature component)
• Milestone added for target branch/version (ex: 32.x for stable32)

AI (if applicable)

• The content of this PR was partly or fully generated using AI