fix: Add custom fields, translations, add app logs to login routes

lib/core/bloc/my_bloc_observer.dart

@@ -0,0 +1,41 @@
+import 'package:flutter_bloc/flutter_bloc.dart';
+import 'package:paperless_mobile/core/bloc/transient_error.dart';
+import 'package:paperless_mobile/core/translation/error_code_localization_mapper.dart';
+import 'package:paperless_mobile/features/logging/data/logger.dart';
+import 'package:paperless_mobile/helpers/message_helpers.dart';
+import 'package:paperless_mobile/routing/navigation_keys.dart';
+
+class MyBlocObserver extends BlocObserver {
+  @override
+  void onError(BlocBase bloc, Object error, StackTrace stackTrace) {
+    if (error is TransientError) {
+      _handleTransientError(bloc, error, stackTrace);
+    }
+    super.onError(bloc, error, stackTrace);
+  }
+
+  void _handleTransientError(
+    BlocBase bloc,
+    TransientError error,
+    StackTrace stackTrace,
+  ) {
+    assert(rootNavigatorKey.currentContext != null);
+    final message = switch (error) {
+      TransientPaperlessApiError(code: var code) => translateError(
+          rootNavigatorKey.currentContext!,
+          code,
+        ),
+      TransientMessageError(message: var message) => message,
+    };
+    final details = switch (error) {
+      TransientPaperlessApiError(details: var details) => details,
+      _ => null,
+    };
+
+    showSnackBar(
+      rootNavigatorKey.currentContext!,
+      message,
+      details: details,
+    );
+  }
+}