fix(content-management): improve error handling in blocs

- Replaced errorMessage with exception in states
- Improved error handling in CreateSourceBloc
- Improved error handling in EditTopicBloc
- Updated exception handling for better clarity
- Used HtHttpException for specific error types

Author: fulleni

lib/content_management/bloc/create_source/create_source_bloc.dart

@@ -51,14 +51,14 @@ class CreateSourceBloc extends Bloc<CreateSourceEvent, CreateSourceState> {
       emit(
         state.copyWith(
           status: CreateSourceStatus.failure,
-          errorMessage: e.message,
+          exception: e,
         ),
       );
     } catch (e) {
       emit(
         state.copyWith(
           status: CreateSourceStatus.failure,
-          errorMessage: e.toString(),
+          exception: UnknownException('An unexpected error occurred: $e'),
         ),
       );
     }
@@ -151,14 +151,14 @@ class CreateSourceBloc extends Bloc<CreateSourceEvent, CreateSourceState> {
       emit(
         state.copyWith(
           status: CreateSourceStatus.failure,
-          errorMessage: e.message,
+          exception: e,
         ),
       );
     } catch (e) {
       emit(
         state.copyWith(
           status: CreateSourceStatus.failure,
-          errorMessage: e.toString(),
+          exception: UnknownException('An unexpected error occurred: $e'),
         ),
       );
     }

lib/content_management/bloc/edit_topic/edit_topic_bloc.dart

@@ -47,14 +47,14 @@ class EditTopicBloc extends Bloc<EditTopicEvent, EditTopicState> {
       emit(
         state.copyWith(
           status: EditTopicStatus.failure,
-          errorMessage: e.message,
+          exception: e,
         ),
       );
     } catch (e) {
       emit(
         state.copyWith(
           status: EditTopicStatus.failure,
-          errorMessage: e.toString(),
+          exception: UnknownException('An unexpected error occurred: $e'),
         ),
       );
     }
@@ -121,7 +121,7 @@ class EditTopicBloc extends Bloc<EditTopicEvent, EditTopicState> {
       emit(
         state.copyWith(
           status: EditTopicStatus.failure,
-          errorMessage: 'Cannot update: Original topic data not loaded.',
+          exception: UnknownException('Cannot update: Original topic data not loaded.'),
         ),
       );
       return;
@@ -152,14 +152,14 @@ class EditTopicBloc extends Bloc<EditTopicEvent, EditTopicState> {
       emit(
         state.copyWith(
           status: EditTopicStatus.failure,
-          errorMessage: e.message,
+          exception: e,
         ),
       );
     } catch (e) {
       emit(
         state.copyWith(
           status: EditTopicStatus.failure,
-          errorMessage: e.toString(),
+          exception: UnknownException('An unexpected error occurred: $e'),
         ),
       );
     }

lib/content_management/bloc/edit_topic/edit_topic_state.dart

@@ -27,7 +27,7 @@ final class EditTopicState extends Equatable {
     this.description = '',
     this.iconUrl = '',
     this.contentStatus = ContentStatus.active,
-    this.errorMessage,
+    this.exception,
     this.updatedTopic,
   });
 
@@ -37,7 +37,7 @@ final class EditTopicState extends Equatable {
   final String description;
   final String iconUrl;
   final ContentStatus contentStatus;
-  final String? errorMessage;
+  final HtHttpException? exception;
   final Topic? updatedTopic;
 
   /// Returns true if the form is valid and can be submitted.
@@ -52,7 +52,7 @@ final class EditTopicState extends Equatable {
     String? description,
     String? iconUrl,
     ContentStatus? contentStatus,
-    String? errorMessage,
+    HtHttpException? exception,
     Topic? updatedTopic,
   }) {
     return EditTopicState(
@@ -62,7 +62,7 @@ final class EditTopicState extends Equatable {
       description: description ?? this.description,
       iconUrl: iconUrl ?? this.iconUrl,
       contentStatus: contentStatus ?? this.contentStatus,
-      errorMessage: errorMessage ?? this.errorMessage,
+      exception: exception,
       updatedTopic: updatedTopic ?? this.updatedTopic,
     );
   }
@@ -75,7 +75,7 @@ final class EditTopicState extends Equatable {
         description,
         iconUrl,
         contentStatus,
-        errorMessage,
+        exception,
         updatedTopic,
       ];
 }