Retention now mirrors the backend: cached stories age out at RECENT_HOURS (72h,
the active feed window), seen/read markers at 96h (window + buffer), and cached
article bodies at 14 days (raw-article retention). Saved bookmarks stay protected.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
CacheMaintenance prunes the SwiftData caches so they don't grow forever:
seen markers >30d, read >90d, cached articles >30d, cached stories >14d —
always protecting saved bookmarks. Runs on launch. Settings gains a
"Clear offline cache" action (keeps saved) with a count + confirmation.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
