refactor: TripDetailView loads games on demand, improve poll UI

- Refactor TripDetailView to fetch games from AppDataProvider when not
  provided, adding loading state indicator for better UX
- Update all callers (25+ HomeContent variants, TripOptionsView, HomeView)
  to use simpler TripDetailView(trip:) initializer
- Fix PollDetailView sheet issue by using sheet(item:) instead of
  sheet(isPresented:) to prevent blank screen on first tap
- Improve PollDetailView UI with Theme styling, icons, and better
  visual hierarchy for share code, voting status, and results sections

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

SportsTime/Features/Home/Views/Variants/Flighty/HomeContent_Flighty.swift

@@ -193,7 +193,7 @@ struct HomeContent_Flighty: View {
             ForEach(savedTrips.prefix(2)) { savedTrip in
                 if let trip = savedTrip.trip {
                     NavigationLink {
-                        TripDetailView(trip: trip, games: savedTrip.games)
+                        TripDetailView(trip: trip)
                     } label: {
                         tripCard(trip)
                     }