fix: hero list cache

Hala was released recently and it doesn't appear in the app despite being in the card database.

The caching logic could be improved somehow or maybe a button that refreshes the list manually

Start by reproducing the missing Hala entry in the app and tracing how the hero list is loaded and cached from the card database. Compare the cached data with the database, then define completion as Hala appearing reliably, with any refresh behavior verified if that becomes part of the chosen fix.

Written by the indexing model from the issue text.