GReader "mark all as read" leaves items unread on the server (Google Reader on Miniflux)

Checklist

• I've already searched in existing issues and haven't found a similar problem reported.
• I'm using the latest version of the app
• This error caused the app to crash
• This error is reproducible

Which category best fits this error?

Feed Sync

App version

0.16.1

Reproduction steps

Google Reader account pointing to a self-hosted Miniflux instance (via its Google Reader API).

Steps to reproduce

1. Open the unread list - e.g. 515 unread.
2. Tap Mark all as read -> count drops to 0.
3. Open the Miniflux web UI in a browser → still shows ~1699 unread.
4. Pull-to-refresh in Read You → count jumps to ~1796 unread.
5. Tap Mark all as read again → count drops to 0.
6. Pull-to-refresh → count rebounds to ~515; Miniflux web UI shows ~475.

Reported previously in this comment: https://github.com/ReadYouApp/ReadYou/issues/1157#issuecomment-3832101605

I will submit pull request that fixes this by using googleReaderAPI.markAllAsRead().

Start by tracing the mark-all-as-read flow in the Android/Kotlin app to the googleReaderAPI.markAllAsRead() entry point named in the report. Reproduce the issue against Miniflux, then verify that marking all items read updates the server and that the unread count stays consistent after refresh.