fix: add SettingsProvider to SpeedometerViewModel and fix ProviderNotFoundException

- SpeedometerViewModel now requires both LocationRepository and SettingsProvider
- SpeedometerView uses SettingsProvider.currentTheme instead of non-existent Theme provider
- main.dart: SettingsProvider created before SpeedometerViewModel in provider hierarchy
- Restores proper DI wiring after layered architecture refactor

lib/ui/features/speedometer/speedometer_view.dart

@@ -5,6 +5,7 @@ import 'package:provider/provider.dart';
 import '../../../core/constants/overlay_constants.dart';
 import '../../../core/theme/color_themes.dart';
 import '../../shared/speed_display.dart';
+import '../../../providers/settings_provider.dart';
 import 'speedometer_view_model.dart';
 
 /// Thin UI view for the speedometer — renders speed and compass.
@@ -19,9 +20,8 @@ class SpeedometerView extends StatelessWidget {
       selector: (_, vm) => vm.displaySpeed,
       builder: (context, displaySpeed, _) {
         final vm = context.watch<SpeedometerViewModel>();
-        final theme = context.select<Theme, ColorTheme>(
-          (theme) => ColorThemes.themes[0],
-        );
+        final settings = context.read<SettingsProvider>();
+        final theme = settings.currentTheme;
 
         // Staleness — UI-layer concern
         final age = DateTime.now().difference(vm.displayData.timestamp);