Implemented Behavior

• Library root remains list-oriented.
• Entering Movies defaults to a compact 5x2 cover grid.
• Entering Series defaults to a compact 5x2 cover grid.
• Multi-season series drill-down defaults the season picker to a compact 5x2 cover grid.
• Pressing A on a compact grid tile opens a Jellyfin metadata detail panel.
• Pressing A inside the detail panel plays the movie or drills into the next series/season level.
• Pressing X exits the detail panel back to the grid.
• Back restores the parent level’s selection, scroll, and view mode.
• Episode lists default to list view for readability.
• Missing/loading poster art uses a styled video placeholder while the existing async poster fetch/decode pipeline catches up.
• Detail panels show core Jellyfin metadata: summary, ratings, genres, studios, played/favorite status, and top cast.