refactor(app_configuration): reorder configuration tabs

- Move General tab to the first position
- Update tab order in TabBar and TabBarView
- Replace placeholder text with actual implementation

Author: fulleni

lib/app_configuration/view/app_configuration_page.dart

@@ -73,9 +73,9 @@ class _AppConfigurationPageState extends State<AppConfigurationPage>
                 tabAlignment: TabAlignment.start,
                 isScrollable: true,
                 tabs: [
+                  Tab(text: l10n.generalTab),
                   Tab(text: l10n.feedTab),
                   Tab(text: l10n.advertisementsTab),
-                  Tab(text: l10n.generalTab),
                 ],
               ),
             ],
@@ -143,23 +143,23 @@ class _AppConfigurationPageState extends State<AppConfigurationPage>
             return TabBarView(
               controller: _tabController,
               children: [
-                FeedConfigurationTab(
+                GeneralConfigurationTab(
                   remoteConfig: remoteConfig,
                   onConfigChanged: (newConfig) {
                     context.read<AppConfigurationBloc>().add(
                       AppConfigurationFieldChanged(remoteConfig: newConfig),
                     );
                   },
                 ),
-                AdvertisementsConfigurationTab(
+                FeedConfigurationTab(
                   remoteConfig: remoteConfig,
                   onConfigChanged: (newConfig) {
                     context.read<AppConfigurationBloc>().add(
                       AppConfigurationFieldChanged(remoteConfig: newConfig),
                     );
                   },
                 ),
-                GeneralConfigurationTab(
+                AdvertisementsConfigurationTab(
                   remoteConfig: remoteConfig,
                   onConfigChanged: (newConfig) {
                     context.read<AppConfigurationBloc>().add(