refactor(data): implement data operation registry for create and read operations

- Introduce DataOperationRegistry for managing data operations
- Replace switch-case statements with registry lookups for create and readAll operations
- Improve extensibility and maintainability of data operation handling

Author: fulleni

routes/api/v1/data/index.dart

@@ -6,6 +6,7 @@ import 'package:dart_frog/dart_frog.dart';
 import 'package:data_repository/data_repository.dart';
 import 'package:flutter_news_app_api_server_full_source_code/src/helpers/response_helper.dart';
 import 'package:flutter_news_app_api_server_full_source_code/src/rbac/permission_service.dart';
+import 'package:flutter_news_app_api_server_full_source_code/src/registry/data_operation_registry.dart';
 import 'package:flutter_news_app_api_server_full_source_code/src/registry/model_registry.dart';
 import 'package:logging/logging.dart';
 import 'package:mongo_dart/mongo_dart.dart';
@@ -165,55 +166,16 @@ Future<PaginatedResponse<dynamic>> _readAllItems(
     'Executing _readAllItems for model "$modelName", userId: $userId.',
   );
   try {
-    switch (modelName) {
-      case 'headline':
-        return await context.read<DataRepository<Headline>>().readAll(
-              userId: userId,
-              filter: filter,
-              sort: sort,
-              pagination: pagination,
-            );
-      case 'topic':
-        return await context.read<DataRepository<Topic>>().readAll(
-              userId: userId,
-              filter: filter,
-              sort: sort,
-              pagination: pagination,
-            );
-      case 'source':
-        return await context.read<DataRepository<Source>>().readAll(
-              userId: userId,
-              filter: filter,
-              sort: sort,
-              pagination: pagination,
-            );
-      case 'country':
-        return await context.read<DataRepository<Country>>().readAll(
-              userId: userId,
-              filter: filter,
-              sort: sort,
-              pagination: pagination,
-            );
-      case 'language':
-        return await context.read<DataRepository<Language>>().readAll(
-              userId: userId,
-              filter: filter,
-              sort: sort,
-              pagination: pagination,
-            );
-      case 'user':
-        return await context.read<DataRepository<User>>().readAll(
-              userId: userId,
-              filter: filter,
-              sort: sort,
-              pagination: pagination,
-            );
-      default:
-        _logger.warning('Unsupported model type "$modelName" for GET all.');
-        throw OperationFailedException(
-          'Unsupported model type "$modelName" for GET all.',
-        );
+    final registry = context.read<DataOperationRegistry>();
+    final reader = registry.allItemsReaders[modelName];
+
+    if (reader == null) {
+      _logger.warning('Unsupported model type "$modelName" for GET all.');
+      throw OperationFailedException(
+        'Unsupported model type "$modelName" for GET all.',
+      );
     }
+    return await reader(context, userId, filter, sort, pagination);
   } catch (e, s) {
     _logger.severe(
       'Unhandled exception in _readAllItems for model "$modelName".',
@@ -237,43 +199,16 @@ Future<dynamic> _createItem(
     'Executing _createItem for model "$modelName", userId: $userId.',
   );
   try {
-    switch (modelName) {
-      case 'headline':
-        return await context.read<DataRepository<Headline>>().create(
-              item: itemToCreate as Headline,
-              userId: userId,
-            );
-      case 'topic':
-        return await context.read<DataRepository<Topic>>().create(
-              item: itemToCreate as Topic,
-              userId: userId,
-            );
-      case 'source':
-        return await context.read<DataRepository<Source>>().create(
-              item: itemToCreate as Source,
-              userId: userId,
-            );
-      case 'country':
-        return await context.read<DataRepository<Country>>().create(
-              item: itemToCreate as Country,
-              userId: userId,
-            );
-      case 'language':
-        return await context.read<DataRepository<Language>>().create(
-              item: itemToCreate as Language,
-              userId: userId,
-            );
-      case 'remote_config':
-        return await context.read<DataRepository<RemoteConfig>>().create(
-              item: itemToCreate as RemoteConfig,
-              userId: userId,
-            );
-      default:
-        _logger.warning('Unsupported model type "$modelName" for POST.');
-        throw OperationFailedException(
-          'Unsupported model type "$modelName" for POST.',
-        );
+    final registry = context.read<DataOperationRegistry>();
+    final creator = registry.itemCreators[modelName];
+
+    if (creator == null) {
+      _logger.warning('Unsupported model type "$modelName" for POST.');
+      throw OperationFailedException(
+        'Unsupported model type "$modelName" for POST.',
+      );
     }
+    return await creator(context, itemToCreate, userId);
   } catch (e, s) {
     _logger.severe(
       'Unhandled exception in _createItem for model "$modelName".',