style(app_configuration): enhance advertisements config layout

- Adjust ExpansionTile children padding for better hierarchy visualization
- Add top and bottom padding to ExpansionTile for improved layout
- Set expandedCrossAxisAlignment to start for consistent content alignment

Author: fulleni

lib/app_configuration/view/tabs/advertisements_configuration_tab.dart

@@ -36,8 +36,11 @@ class AdvertisementsConfigurationTab extends StatelessWidget {
         ExpansionTile(
           title: Text(l10n.adPlatformConfigurationTitle),
           childrenPadding: const EdgeInsetsDirectional.only(
-            start: AppSpacing.xxl,
+            start: AppSpacing.lg, // Adjusted padding for hierarchy
+            top: AppSpacing.md,
+            bottom: AppSpacing.md,
           ),
+          expandedCrossAxisAlignment: CrossAxisAlignment.start, // Align content to start
           children: [
             AdPlatformConfigForm(
               remoteConfig: remoteConfig,
@@ -50,8 +53,11 @@ class AdvertisementsConfigurationTab extends StatelessWidget {
         ExpansionTile(
           title: Text(l10n.feedAdSettingsTitle),
           childrenPadding: const EdgeInsetsDirectional.only(
-            start: AppSpacing.xxl,
+            start: AppSpacing.lg, // Adjusted padding for hierarchy
+            top: AppSpacing.md,
+            bottom: AppSpacing.md,
           ),
+          expandedCrossAxisAlignment: CrossAxisAlignment.start, // Align content to start
           children: [
             FeedAdSettingsForm(
               remoteConfig: remoteConfig,
@@ -64,8 +70,11 @@ class AdvertisementsConfigurationTab extends StatelessWidget {
         ExpansionTile(
           title: Text(l10n.articleAdSettingsTitle),
           childrenPadding: const EdgeInsetsDirectional.only(
-            start: AppSpacing.xxl,
+            start: AppSpacing.lg, // Adjusted padding for hierarchy
+            top: AppSpacing.md,
+            bottom: AppSpacing.md,
           ),
+          expandedCrossAxisAlignment: CrossAxisAlignment.start, // Align content to start
           children: [
             ArticleAdSettingsForm(
               remoteConfig: remoteConfig,