I’m sorry @k3b, I see your message on Reddit modmail now but I’m afraid it had escaped me completely.
I’ve now implemented what you asked and after some errors that stopped updates from being posted entirely at first, it seems to work now except that linking to the home page doesn’t work if there is no home page listed, so right now that example looks pretty bad, but next time, it should fallback to the source code link instead of going “None”.
I’ve made it so new apps are followed by their app summary, while updated apps are followed by their version number, and all apps (attempt to) link to their home page.
The code to the whole bot is not public as it’s honestly a big mess that, as @Izzy mentions, does a bunch of other things. I can send you or post the F-Droid part though if you want to improve it further, just don’t expect nice code and keep in mind you won’t be able to actually run it yourself without a bunch of other modules that would need to be pruned of… things… before posting.