refactor(theme): update color references to use AppColors for consistency across components

lib/core/widgets/themed_loading_screen.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import '../theme/app_colors.dart';
 
 class ThemedLoading extends StatelessWidget {
   const ThemedLoading({super.key});
@@ -11,8 +12,8 @@ class ThemedLoading extends StatelessWidget {
           begin: Alignment.topLeft,
           end: Alignment.bottomRight,
           colors: [
-            Color(0xFF0F1014), // Deep Space Dark
-            Color(0xFF181920), // Soft Eerie Black
+            AppColors.background,
+            AppColors.backgroundAlt,
           ],
         ),
       ),
@@ -21,15 +22,15 @@ class ThemedLoading extends StatelessWidget {
           mainAxisSize: MainAxisSize.min,
           children: [
             const CircularProgressIndicator(
-              color: Color(0xFF007AFF), // Electric Blue (AppColors.primary)
+              color: AppColors.primary,
               strokeWidth: 3,
             ),
             const SizedBox(height: 16),
             Text(
               'Loading...',
               style: TextStyle(
-                fontFamily: 'Outfit', // Match AppTheme
-                color: Colors.white.withOpacity(0.7),
+                fontFamily: 'Outfit',
+                color: AppColors.textSecondary,
                 fontSize: 14,
               ),
             ),