[Feature Request] Feed list: date in headline <-> feed items date

**Describe the bug**
The date from the "headline" is the date when the feed was fetched (right now) but the feed items are much more older

**To Reproduce**
Steps to reproduce the behavior:
1. use this feed: https://fransdejonge.com/category/media/drawing/feed/
2. see the list

**Expected behavior**
The date in the headline is the same date of the feed items

(if a feed items is older than 1 year it would be fine to have a summarizing headline "older than 1 year")

**Environment information (please complete the following information):**
- FreshRSS version: 1.18.1