Redesign watchlist with Movies and Series rows

[chillpill244]

Summary

• Replaces the flat grid with two horizontal rows — Movies and Series — split by media type
• WatchlistUiState now holds separate movies and series lists; all state emissions updated accordingly
• Manual D-pad focus tracking (isFocusedOverride / enableSystemFocus = false) for reliable TV remote navigation
• Long-press Enter removes an item; a -1L sentinel on enterKeyDownTimeMs prevents spurious removal when navigating to the screen
• Mobile: larger cards, 48dp top padding, focus highlight suppressed on touch devices
• TV: spacing tuned so both rows fit on screen; contentPadding on LazyRow prevents clipping of focused cards at the left edge

Test plan

• Open watchlist on TV — Movies and Series rows appear, D-pad navigates correctly between rows and to the top bar
• Navigate to watchlist from another screen — first item is not removed on entry
• Open watchlist on mobile — no focus highlight, cards and headings are appropriately sized
• Watchlist with only movies or only series — single row renders correctly
• Empty watchlist — empty state shown with bookmark icon

🤖 Generated with Claude Code

[chillpill244]