perf: lazy hierarchical loading for game picker

Replace upfront loading of all games with lazy Sport → Team → Game
hierarchy. Games are now fetched per-team when expanded and cached
to prevent re-fetching. Also removes pagination workaround and
pre-computes groupings in ScheduleViewModel to avoid per-render work.

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

SportsTime/Features/Schedule/Views/ScheduleListView.swift

@@ -10,13 +10,17 @@ struct ScheduleListView: View {
     @State private var viewModel = ScheduleViewModel()
     @State private var showDatePicker = false
 
+    private var allGames: [RichGame] {
+        viewModel.gamesBySport.flatMap(\.games)
+    }
+
     var body: some View {
         Group {
-            if viewModel.isLoading && viewModel.displayedGames.isEmpty {
+            if viewModel.isLoading && allGames.isEmpty {
                 loadingView
             } else if let errorMessage = viewModel.errorMessage {
                 errorView(message: errorMessage)
-            } else if viewModel.displayedGames.isEmpty {
+            } else if allGames.isEmpty {
                 emptyView
             } else {
                 gamesList
@@ -96,12 +100,6 @@ struct ScheduleListView: View {
                 Section {
                     ForEach(sportGroup.games) { richGame in
                         GameRowView(game: richGame, showDate: true, showLocation: true)
-                            .onAppear {
-                                // Trigger load more when the last game appears
-                                if richGame.id == viewModel.lastDisplayedGame?.id {
-                                    viewModel.loadMoreGames()
-                                }
-                            }
                     }
                 } header: {
                     HStack(spacing: 8) {
@@ -112,18 +110,6 @@ struct ScheduleListView: View {
                 }
                 .listRowBackground(Theme.cardBackground(colorScheme))
             }
-
-            // Show loading indicator when more games are available
-            if viewModel.hasMoreGames {
-                Section {
-                    HStack {
-                        Spacer()
-                        ProgressView()
-                        Spacer()
-                    }
-                    .listRowBackground(Color.clear)
-                }
-            }
         }
         .listStyle(.plain)
         .scrollContentBackground(.hidden)
@@ -231,6 +217,14 @@ struct GameRowView: View {
     var showDate: Bool = false
     var showLocation: Bool = false
 
+    // Static formatter to avoid allocation per row (significant performance improvement)
+    private static let dateFormatter: DateFormatter = {
+        let formatter = DateFormatter()
+        formatter.dateFormat = "EEE, MMM d"
+        return formatter
+    }()
+
+    // Cache isToday check to avoid repeated Calendar calls
     private var isToday: Bool {
         Calendar.current.isDateInToday(game.game.dateTime)
     }
@@ -240,7 +234,7 @@ struct GameRowView: View {
             // Date (when grouped by sport)
             if showDate {
                 HStack(spacing: 6) {
-                    Text(formattedDate)
+                    Text(Self.dateFormatter.string(from: game.game.dateTime))
                         .font(.caption)
                         .fontWeight(.medium)
                         .foregroundStyle(.secondary)
@@ -300,12 +294,6 @@ struct GameRowView: View {
         .padding(.vertical, 4)
         .listRowBackground(isToday ? Color.orange.opacity(0.1) : nil)
     }
-
-    private var formattedDate: String {
-        let formatter = DateFormatter()
-        formatter.dateFormat = "EEE, MMM d"
-        return formatter.string(from: game.game.dateTime)
-    }
 }
 
 // MARK: - Team Badge