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/extension/app_snack_bar.dart

@@ -37,7 +37,7 @@ extension AppSnackBarsBuildContextExtension on BuildContext {
           Text(
             message,
             style: textTheme.bodyMedium?.copyWith(
-              color: ColorsManager.whiteColors,
+              color: ColorsManager.white,
             ),
           ),
         ],

lib/utils/extension/build_context_x.dart

@@ -49,7 +49,7 @@ extension BuildContextExt on BuildContext {
                   title,
                   style: titleStyle ??
                       context.textTheme.bodyMedium!.copyWith(
-                        color: ColorsManager.primaryColorWithOpacity,
+                        color: ColorsManager.opaquePrimary,
                         fontWeight: FontWeight.bold,
                       ),
                 ),
@@ -87,8 +87,8 @@ extension BuildContextExt on BuildContext {
                               child: Text(
                                 onDismissText ?? 'Cancel',
                                 style: context.textTheme.bodyMedium!.copyWith(
-                                    color: onDismissColor ??
-                                        ColorsManager.greyColor),
+                                    color:
+                                        onDismissColor ?? ColorsManager.greyColor),
                               ),
                             ),
                           ),
@@ -104,7 +104,7 @@ extension BuildContextExt on BuildContext {
                                 onConfirmText ?? 'Confirm',
                                 style: context.textTheme.bodyMedium!.copyWith(
                                     color: onConfirmColor ??
-                                        ColorsManager.primaryColorWithOpacity),
+                                        ColorsManager.opaquePrimary),
                               ),
                             ),
                           ),