fix: Fix grouping links by dates and forgetting URL status on link deletion

[marienfressinaud]

Related issue(s)

N/A

How to test manually

1. Make sure to have a link being saved as '2026-06-24 23:30:00+00' in the database in a feed that you follow while your timezone is set to something like Europe/Paris
2. Refresh the news
3. Make sure the link is displayed as being published the day after, 25th June 2026 at 01:30
4. Verify that it is present in the correct date group and that you can mark it as read from the date actions
5. Delete the link
6. Verify there is not any more a corresponding UrlStatus in the database

Reviewer checklist

• Code is manually tested
• Interface works on both mobiles and big screens
• Interface works in both light and dark modes
• Interface works on both Firefox and Chrome
• Accessibility has been tested
• Translations are synchronized
• The API provides the corresponding endpoints / data
• Tests are up to date
• Copyright notices are up to date
• Documentation is up to date
• Pull request has been reviewed and approved