Review follow-ups (Greptile):
- Without the Navigation API (older Safari and Firefox) back() always
called Location.back(), so a page that opened the session still left
the app. The service now tracks the router's in-app history depth there
(trackRouterHistoryDepth): first navigation 0, push +1, replacement
keeps it, a traversal restores the depth recorded for its entry. Depth
0 opens the parent; an unknown depth (an entry from before a reload)
keeps Location.back().
- Stalker's Discover (movie/tv section), actor and search pages now have
tests that they hand the service the parent under the portal :id.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>