type: added
area: immersion

- Added a local stats dashboard for immersion tracking with Overview, Anime, Trends, Vocabulary, and Sessions views.
- Added anime progress, episode completion, Anki card links, and occurrence drill-down across the stats dashboard.
- Added richer session timelines with new-word activity, cumulative totals, and pause/seek/card event markers.
- Added completed-episodes and completed-anime totals to the Overview tracking snapshot.