feat(app_configuration): add general configuration tab

- Implement GeneralConfigurationTab widget for App Configuration page
- Add maintenance mode and force update settings sections
- Include SwitchListTile and text input for configuration options
- Use ExpansionTile for collapsible sections
- Implement localization support for all UI elements

Author: fulleni

lib/app_configuration/view/tabs/general_configuration_tab.dart

@@ -0,0 +1,153 @@
+import 'package:core/core.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_bloc/flutter_bloc.dart';
+import 'package:flutter_news_app_web_dashboard_full_source_code/app_configuration/bloc/app_configuration_bloc.dart';
+import 'package:flutter_news_app_web_dashboard_full_source_code/app_configuration/widgets/app_config_form_fields.dart';
+import 'package:flutter_news_app_web_dashboard_full_source_code/l10n/l10n.dart';
+import 'package:ui_kit/ui_kit.dart';
+
+/// {@template general_configuration_tab}
+/// A widget representing the "General" tab in the App Configuration page.
+///
+/// This tab allows configuration of maintenance mode and force update settings.
+/// {@endtemplate}
+class GeneralConfigurationTab extends StatelessWidget {
+  /// {@macro general_configuration_tab}
+  const GeneralConfigurationTab({
+    required this.remoteConfig,
+    required this.onConfigChanged,
+    super.key,
+  });
+
+  /// The current [RemoteConfig] object.
+  final RemoteConfig remoteConfig;
+
+  /// Callback to notify parent of changes to the [RemoteConfig].
+  final ValueChanged<RemoteConfig> onConfigChanged;
+
+  @override
+  Widget build(BuildContext context) {
+    final l10n = AppLocalizationsX(context).l10n;
+
+    return ListView(
+      padding: const EdgeInsets.all(AppSpacing.lg),
+      children: [
+        // Top-level ExpansionTile for Maintenance Section
+        ExpansionTile(
+          title: Text(l10n.maintenanceModeTitle),
+          childrenPadding: const EdgeInsets.symmetric(
+            horizontal: AppSpacing.xxl,
+            vertical: AppSpacing.md,
+          ),
+          children: [
+            Column(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Text(
+                  l10n.maintenanceModeDescription,
+                  style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                    color: Theme.of(context).colorScheme.onSurface.withOpacity(0.7),
+                  ),
+                ),
+                const SizedBox(height: AppSpacing.lg),
+                SwitchListTile(
+                  title: Text(l10n.isUnderMaintenanceLabel),
+                  subtitle: Text(l10n.isUnderMaintenanceDescription),
+                  value: remoteConfig.appStatus.isUnderMaintenance,
+                  onChanged: (value) {
+                    onConfigChanged(
+                      remoteConfig.copyWith(
+                        appStatus: remoteConfig.appStatus.copyWith(
+                          isUnderMaintenance: value,
+                        ),
+                      ),
+                    );
+                  },
+                ),
+              ],
+            ),
+          ],
+        ),
+        const SizedBox(height: AppSpacing.lg),
+        // Top-level ExpansionTile for Force Update Section
+        ExpansionTile(
+          title: Text(l10n.forceUpdateTitle),
+          childrenPadding: const EdgeInsets.symmetric(
+            horizontal: AppSpacing.xxl,
+            vertical: AppSpacing.md,
+          ),
+          children: [
+            Column(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Text(
+                  l10n.forceUpdateDescription,
+                  style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                    color: Theme.of(context).colorScheme.onSurface.withOpacity(0.7),
+                  ),
+                ),
+                const SizedBox(height: AppSpacing.lg),
+                AppConfigTextField(
+                  label: l10n.latestAppVersionLabel,
+                  description: l10n.latestAppVersionDescription,
+                  value: remoteConfig.appStatus.latestAppVersion,
+                  onChanged: (value) {
+                    onConfigChanged(
+                      remoteConfig.copyWith(
+                        appStatus: remoteConfig.appStatus.copyWith(
+                          latestAppVersion: value,
+                        ),
+                      ),
+                    );
+                  },
+                ),
+                SwitchListTile(
+                  title: Text(l10n.isLatestVersionOnlyLabel),
+                  subtitle: Text(l10n.isLatestVersionOnlyDescription),
+                  value: remoteConfig.appStatus.isLatestVersionOnly,
+                  onChanged: (value) {
+                    onConfigChanged(
+                      remoteConfig.copyWith(
+                        appStatus: remoteConfig.appStatus.copyWith(
+                          isLatestVersionOnly: value,
+                        ),
+                      ),
+                    );
+                  },
+                ),
+                AppConfigTextField(
+                  label: l10n.iosUpdateUrlLabel,
+                  description: l10n.iosUpdateUrlDescription,
+                  value: remoteConfig.appStatus.iosUpdateUrl,
+                  onChanged: (value) {
+                    onConfigChanged(
+                      remoteConfig.copyWith(
+                        appStatus: remoteConfig.appStatus.copyWith(
+                          iosUpdateUrl: value,
+                        ),
+                      ),
+                    );
+                  },
+                ),
+                AppConfigTextField(
+                  label: l10n.androidUpdateUrlLabel,
+                  description: l10n.androidUpdateUrlDescription,
+                  value: remoteConfig.appStatus.androidUpdateUrl,
+                  onChanged: (value) {
+                    onConfigChanged(
+                      remoteConfig.copyWith(
+                        appStatus: remoteConfig.appStatus.copyWith(
+                          androidUpdateUrl: value,
+                        ),
+                      ),
+                    );
+                  },
+                ),
+              ],
+            ),
+          ],
+        ),
+      ],
+    );
+  }
+}