fix: 22 audit fixes — concurrency, memory, performance, accessibility

- Move 7 Data(contentsOf:) calls off MainActor via Task.detached (BootstrapService)
- Batch-fetch N+1 queries in sync merge loops (CanonicalSyncService)
- Predicate-based gamesForTeam fetch instead of fetching all games (DataProvider)
- Proper Sendable on RouteInfo with nonisolated(unsafe) polyline (LocationService)
- [weak self] in BGTaskScheduler register closures (BackgroundSyncManager)
- Cache tripDays, routeWaypoints as @State with recompute (TripDetailView)
- Remove unused AnyCancellable, add Task lifecycle management (TripDetailView)
- Cache sportStadiums, recentVisits as stored properties (ProgressViewModel)
- Dynamic Type fonts replacing hardcoded sizes (OnboardingPaywallView)
- Accessibility labels/hints on stadium picker, date picker, map, stats,
  settings toggle, and day cards

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

SportsTime/Features/Progress/ViewModels/ProgressViewModel.swift

@@ -49,10 +49,8 @@ final class ProgressViewModel {
     /// Pre-computed progress fractions per sport (avoids filtering visits per sport per render)
     private(set) var sportProgressFractions: [Sport: Double] = [:]
 
-    /// Stadiums for the selected sport
-    var sportStadiums: [Stadium] {
-        stadiums.filter { $0.sport == selectedSport }
-    }
+    /// Stadiums for the selected sport (cached, recomputed on data change)
+    private(set) var sportStadiums: [Stadium] = []
 
     /// Count of trips for the selected sport (stub - can be enhanced)
     var tripCount: Int {
@@ -60,30 +58,8 @@ final class ProgressViewModel {
         0
     }
 
-    /// Recent visits sorted by date
-    var recentVisits: [VisitSummary] {
-        visits
-            .sorted { $0.visitDate > $1.visitDate }
-            .prefix(10)
-            .compactMap { visit -> VisitSummary? in
-                guard let stadium = dataProvider.stadium(for: visit.stadiumId),
-                      let sport = visit.sportEnum else {
-                    return nil
-                }
-                return VisitSummary(
-                    id: visit.id,
-                    stadium: stadium,
-                    visitDate: visit.visitDate,
-                    visitType: visit.visitType,
-                    sport: sport,
-                    homeTeamName: visit.homeTeamName,
-                    awayTeamName: visit.awayTeamName,
-                    score: visit.finalScore,
-                    photoCount: visit.photoMetadata?.count ?? 0,
-                    notes: visit.notes
-                )
-            }
-    }
+    /// Recent visits sorted by date (cached, recomputed on data change)
+    private(set) var recentVisits: [VisitSummary] = []
 
     // MARK: - Configuration
 
@@ -154,7 +130,8 @@ final class ProgressViewModel {
 
     private func recomputeDerivedState() {
         // Compute league progress once
-        let sportStadiums = stadiums.filter { $0.sport == selectedSport }
+        let filteredStadiums = stadiums.filter { $0.sport == selectedSport }
+        self.sportStadiums = filteredStadiums
 
         let visitedStadiumIds = Set(
             visits
@@ -164,12 +141,12 @@ final class ProgressViewModel {
                 }
         )
 
-        let visited = sportStadiums.filter { visitedStadiumIds.contains($0.id) }
-        let remaining = sportStadiums.filter { !visitedStadiumIds.contains($0.id) }
+        let visited = filteredStadiums.filter { visitedStadiumIds.contains($0.id) }
+        let remaining = filteredStadiums.filter { !visitedStadiumIds.contains($0.id) }
 
         leagueProgress = LeagueProgress(
             sport: selectedSport,
-            totalStadiums: sportStadiums.count,
+            totalStadiums: filteredStadiums.count,
             visitedStadiums: visited.count,
             stadiumsVisited: visited,
             stadiumsRemaining: remaining
@@ -216,6 +193,33 @@ final class ProgressViewModel {
             let visited = min(sportCounts[sport] ?? 0, total)
             return (sport, total > 0 ? Double(visited) / Double(total) : 0)
         })
+
+        // Recompute recent visits cache
+        recomputeRecentVisits()
+    }
+
+    private func recomputeRecentVisits() {
+        recentVisits = visits
+            .sorted { $0.visitDate > $1.visitDate }
+            .prefix(10)
+            .compactMap { visit -> VisitSummary? in
+                guard let stadium = dataProvider.stadium(for: visit.stadiumId),
+                      let sport = visit.sportEnum else {
+                    return nil
+                }
+                return VisitSummary(
+                    id: visit.id,
+                    stadium: stadium,
+                    visitDate: visit.visitDate,
+                    visitType: visit.visitType,
+                    sport: sport,
+                    homeTeamName: visit.homeTeamName,
+                    awayTeamName: visit.awayTeamName,
+                    score: visit.finalScore,
+                    photoCount: visit.photoMetadata?.count ?? 0,
+                    notes: visit.notes
+                )
+            }
     }
 
     // MARK: - Progress Card Generation

SportsTime/Features/Progress/Views/ProgressTabView.swift

@@ -247,6 +247,8 @@ struct ProgressTabView: View {
                     label: "Complete"
                 )
             }
+            .accessibilityElement(children: .ignore)
+            .accessibilityLabel("Statistics: \(progress.visitedStadiums) visited, \(progress.totalStadiums - progress.visitedStadiums) remaining, \(String(format: "%.0f", progress.completionPercentage)) percent complete")
         }
         .padding(Theme.Spacing.lg)
         .background(Theme.cardBackground(colorScheme))

SportsTime/Features/Progress/Views/StadiumVisitSheet.swift

@@ -114,6 +114,8 @@ struct StadiumVisitSheet: View {
                                 .foregroundStyle(Theme.textMuted(colorScheme))
                         }
                     }
+                    .accessibilityLabel(selectedStadium != nil ? "Stadium: \(selectedStadium!.name)" : "Select stadium")
+                    .accessibilityHint("Opens stadium picker")
                 } header: {
                     Text("Location")
                 }
@@ -122,6 +124,7 @@ struct StadiumVisitSheet: View {
                 // Visit Details Section
                 Section {
                     DatePicker("Date", selection: $visitDate, displayedComponents: .date)
+                        .accessibilityHint("Select the date you visited this stadium")
 
                     Picker("Visit Type", selection: $visitType) {
                         ForEach(VisitType.allCases, id: \.self) { type in