Refactor color management and UI components for consistency

- Updated color references in various widgets to use the new `opaquePrimary` color for better visual consistency.
- Refactored `ColorsManager` to improve color definitions and removed redundant color declarations.
- Enhanced UI elements across multiple dialogs and widgets to ensure a cohesive design language.

This change promotes maintainability and aligns with the updated color scheme.

lib/utils/theme/responsive_text_theme.dart

@@ -24,7 +24,7 @@ class ResponsiveTextTheme extends ThemeExtension<ResponsiveTextTheme> {
           deviceManagementTitle: TextStyle(
               fontSize: isMobile ? 20 : 30,
               fontWeight: FontWeight.w700,
-              color: ColorsManager.whiteColors),
+              color: ColorsManager.white),
         );
   }
 }

lib/utils/theme/theme.dart

@@ -7,7 +7,7 @@ final myTheme = ThemeData(
   textTheme: const TextTheme(
     bodySmall: TextStyle(
       fontSize: 13,
-      color: ColorsManager.whiteColors,
+      color: ColorsManager.white,
       fontWeight: FontWeight.normal,
     ),
     bodyMedium: TextStyle(color: Colors.black87, fontSize: 14),
@@ -30,13 +30,13 @@ final myTheme = ThemeData(
       if (states.contains(WidgetState.selected)) {
         return ColorsManager.blueColor;
       }
-      return ColorsManager.whiteColors;
+      return ColorsManager.white;
     }),
     trackColor: WidgetStateProperty.resolveWith((states) {
       if (states.contains(WidgetState.selected)) {
         return ColorsManager.blueColor.withOpacity(0.5);
       }
-      return ColorsManager.whiteColors;
+      return ColorsManager.white;
     }),
   ),
   checkboxTheme: CheckboxThemeData(
@@ -47,12 +47,12 @@ final myTheme = ThemeData(
       return Colors.grey.shade200;
     }),
     checkColor: WidgetStateProperty.all(Colors.white),
-    side: const BorderSide(color: ColorsManager.whiteColors),
+    side: const BorderSide(color: ColorsManager.white),
     shape: RoundedRectangleBorder(
       borderRadius: BorderRadius.circular(4),
     ),
   ),
   dialogTheme: const DialogThemeData(
-    backgroundColor: ColorsManager.whiteColors,
+    backgroundColor: ColorsManager.white,
   ),
 );