feat(ui): replace loading indicators with Apple-style LoadingSpinner

- Add LoadingSpinner component with small/medium/large sizes using system gray color
- Add LoadingPlaceholder for skeleton loading states
- Add LoadingSheet for full-screen blocking overlays
- Replace ThemedSpinner/ThemedSpinnerCompact across all views
- Remove deprecated loading components from AnimatedComponents.swift
- Delete LoadingTextGenerator.swift
- Fix PhotoImportView layout to fill full width

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

SportsTime/Features/Progress/Views/StadiumVisitHistoryView.swift

@@ -14,7 +14,7 @@ struct StadiumVisitHistoryView: View {
         NavigationStack {
             Group {
                 if isLoading {
-                    ProgressView()
+                    LoadingSpinner(size: .medium)
                 } else if visits.isEmpty {
                     EmptyVisitHistoryView()
                 } else {