refactor: update providers to use keepAlive for enhanced state management

- Changed multiple provider annotations to `@Riverpod(keepAlive: true)` to improve state retention and management across the application.
- This update aligns with recent enhancements in state management practices, ensuring better performance and user experience throughout the app.

lib/features/prompts/providers/prompts_providers.dart

@@ -5,14 +5,14 @@ import 'package:conduit/core/services/prompts_service.dart';
 
 part 'prompts_providers.g.dart';
 
-@riverpod
+@Riverpod(keepAlive: true)
 Future<List<Prompt>> promptsList(Ref ref) async {
   final promptsService = ref.watch(promptsServiceProvider);
   if (promptsService == null) return const <Prompt>[];
   return promptsService.getPrompts();
 }
 
-@riverpod
+@Riverpod(keepAlive: true)
 class ActivePromptCommand extends _$ActivePromptCommand {
   @override
   String? build() => null;