Improve UI consistency and add heart save button

- Add themed background to all tab views (Schedule, Settings, My Trips)
- Remove navigation titles from all screens (tab bar provides context)
- Add empty state to My Trips view
- Remove max driving hours slider from trip planner (available in Settings)
- Replace save menu with heart button overlay on trip detail map
- Add ability to unsave trips by tapping heart again

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

SportsTime/Features/Schedule/Views/ScheduleListView.swift

@@ -21,8 +21,9 @@ struct ScheduleListView: View {
                 gamesList
             }
         }
-        .navigationTitle("Schedule")
         .searchable(text: $viewModel.searchText, prompt: "Search teams or venues")
+        .scrollContentBackground(.hidden)
+        .themedBackground()
         .toolbar {
             ToolbarItem(placement: .primaryAction) {
                 Menu {