feat: rebuild desktop UI to match Figma + website, hero slider improvements

- Desktop sidebar (262px, blue gradient, white pill nav), topbar (search + bell + avatar), responsive shell rewritten
- Desktop homepage: immersive hero with Ken Burns animation, pill category chips, date badge cards matching mvnew.eventifyplus.com/home
- Desktop calendar: 60/40 two-column layout with white background
- Desktop profile: full-width banner + 3-column event grids
- Desktop learn more: hero image + about/venue columns + gallery strip
- Desktop settings/contribute: polished to match design system
- Mobile hero slider: RepaintBoundary, animated dots with 44px tap targets, 5s auto-scroll, 8s post-swipe delay, shimmer loading, dynamic event type badge, human-readable dates
- Guest access: requiresAuth false on read endpoints
- Location fix: show place names instead of lat/lng coordinates
- Version 1.6.1+17

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docs/landscape_changes.csv

@@ -0,0 +1,27 @@
+Phase,File,Action,Priority,Description
+1,lib/core/constants.dart,MODIFY,Critical,"Add desktop breakpoints: wideDesktopBreakpoint=1200, sidebarExpandedWidth=240, sidebarCollapsedWidth=72, topBarHeight=64"
+1,lib/widgets/desktop_sidebar.dart,CREATE,Critical,"Collapsible sidebar with icon-only (820-1200px) and full (1200px+) modes, AnimatedContainer transitions"
+1,lib/widgets/desktop_topbar.dart,CREATE,Critical,"Responsive top bar with LayoutBuilder: search field, notifications, avatar, location"
+1,lib/widgets/responsive_shell.dart,CREATE,Critical,"Master responsive scaffold wrapping all desktop screens: sidebar + topbar + content"
+1,lib/screens/responsive_layout.dart,MODIFY,High,"Add three-tier breakpoint support (mobile/tablet/desktop) and ScreenSize enum"
+1,lib/main.dart,MODIFY,Critical,"Update StartupScreen to use ResponsiveShell for desktop routing"
+2,lib/screens/home_desktop_screen.dart,REWRITE,Critical,"Split 1077-line monolith into thin orchestrator + focused content widget"
+2,lib/screens/home_desktop_screen.dart,REWRITE,Critical,"Replace marquee with rich hero carousel (PageView.builder matching mobile)"
+2,lib/screens/home_desktop_screen.dart,REWRITE,Critical,"Replace fixed 3-column grid with SliverGrid + SliverGridDelegateWithMaxCrossAxisExtent"
+2,lib/screens/home_desktop_screen.dart,REWRITE,High,"Add MouseRegion + SystemMouseCursors.click on all tappable cards"
+3,lib/screens/desktop_login_screen.dart,REWRITE,High,"Video background + glassmorphism card matching mobile login style"
+3,lib/screens/desktop_login_screen.dart,REWRITE,High,"Continue as Guest button prominent"
+4,lib/screens/calendar_screen.dart,MODIFY,Medium,"Remove LandscapeShell; use Row with Card-based calendar left + event list right inside ResponsiveShell"
+4,lib/screens/calendar_screen.dart,MODIFY,Medium,"New _eventCardLandscape() with larger images (200px), full title, date, location"
+4,lib/screens/profile_screen.dart,MODIFY,Medium,"Remove LandscapeShell; Row with profile card left + tabbed events right"
+4,lib/screens/profile_screen.dart,MODIFY,Medium,"DefaultTabController with Ongoing/Upcoming/Past tabs + SliverList per tab"
+4,lib/screens/contribute_screen.dart,MODIFY,Medium,"Remove LandscapeShell; Row with contributor info/nav left + tab content right"
+4,lib/screens/contribute_screen.dart,MODIFY,Medium,"Vertical nav list for landscape tabs instead of horizontal TabBar"
+4,lib/screens/settings_screen.dart,MODIFY,Medium,"Remove LandscapeShell; Row with settings nav left + content right"
+4,lib/screens/settings_screen.dart,MODIFY,Medium,"Fix logout navigation to use unified approach"
+4,lib/screens/search_screen.dart,MODIFY,Medium,"Add landscape layout: full-width search bar + Row(popular cities, results)"
+4,lib/screens/learn_more_screen.dart,MODIFY,Low,"Replace hard-coded 820 with AppConstants; add RepaintBoundary; LayoutBuilder for height"
+5,lib/widgets/landscape_shell.dart,DELETE,High,"Replaced by responsive_shell.dart"
+5,lib/widgets/landscape_section_header.dart,DELETE or REWRITE,Low,"Generalize into SectionHeader or delete if unused"
+5,lib/core/app_decoration.dart,MODIFY,Low,"Add desktop-specific decorations: cardShadow, sidebarDecoration, topBarShadow"
+8,lib/features/events/services/events_service.dart,MODIFY,Critical,"Set requiresAuth: false on getEventTypes, getEventsByPincode, getEventDetails, getEventsByMonthYear"