feat: Update theme colors and add Today Schedule screen

- Changed color scheme from ShadBlueColorScheme to ShadZincColorScheme in main.dart
- Added getMostRecentIntake method in SupplementProvider to retrieve the latest intake for a supplement
- Integrated TodayScheduleScreen into HomeScreen with a new BottomNavigationBar item
- Updated SupplementsListScreen title and adjusted layout for better UX
- Enhanced SupplementCard to support undoing last taken action and improved popover menu options
- Added popover package for better UI interactions

lib/providers/supplement_provider.dart

@@ -367,6 +367,24 @@ class SupplementProvider with ChangeNotifier, WidgetsBindingObserver {
     return _todayIntakes.where((intake) => intake['supplement_id'] == supplementId).length;
   }
 
+  /// Get the most recent intake for a supplement today
+  Map<String, dynamic>? getMostRecentIntake(int supplementId) {
+    final supplementIntakes = _todayIntakes
+        .where((intake) => intake['supplement_id'] == supplementId)
+        .toList();
+
+    if (supplementIntakes.isEmpty) return null;
+
+    // Sort by takenAt time (most recent first)
+    supplementIntakes.sort((a, b) {
+      final aTime = DateTime.parse(a['takenAt']);
+      final bTime = DateTime.parse(b['takenAt']);
+      return bTime.compareTo(aTime); // Descending order
+    });
+
+    return supplementIntakes.first;
+  }
+
   Map<String, double> get dailyIngredientIntake {
     final Map<String, double> ingredientIntake = {};