Published article not appearing on publication site or RSS feed

I published an article on my Hashnode publication (lastdayonearthonpc.hashnode.dev), but it is not showing up on the live site or in the RSS feed.

Details:
- Publication: lastdayonearthonpc.hashnode.dev
- The article editor shows "Published" status with a green checkmark
- However, the publication homepage (lastdayonearthonpc.hashnode.dev) shows "I haven't started writing yet" instead of the article
- The RSS feed (lastdayonearthonpc.hashnode.dev/rss.xml) contains no entries for the article
- I tried the following, but the issue persists:
1. Republishing via the "Update" button multiple times
2. Hard-refreshing the browser (Ctrl+Shift+R)
3. Waiting 20+ minutes for cache/propagation
4. Checking the Visibility settings (Hide from feed, Disable comments — all unchecked/normal)

This appears to be a backend sync issue where the article is marked as published but is not actually registered in the publication's post list or RSS feed.

Please let me know if you need any additional information or screenshots.

Start by reproducing the issue through the article editor, the publication homepage at lastdayonearthonpc.hashnode.dev, and its /rss.xml endpoint. Check whether the published article is present in the publication post list and RSS generation path; done means it appears on the homepage and as an RSS without manual republishing.

索引モデルが issue の本文から書いたものです。