type: changed area: stats - Sessions are rolled up per episode within each day, with a bulk delete that wipes every session in the group. - Trends add a 365-day range next to the existing 7d/30d/90d/all options. - Library detail view gets a delete-episode action that removes the video and all its sessions. - Vocabulary Top 50 tightens the word/reading column so katakana entries no longer push the scores off screen. - Episode detail hides card events whose Anki notes have been deleted, instead of showing phantom mining activity. - Trend and watch-time charts share a unified theme with horizontal gridlines and larger ticks for legibility. - Overview, Library, Trends, Sessions, and Vocabulary now use generic "title" wording so YouTube videos and anime live comfortably side by side in the dashboard.