TF-3804 Thread Detail Load selected email in parallel with thread metadata

lib/features/thread_detail/domain/state/get_emails_by_ids_state.dart

@@ -24,6 +24,10 @@ class GetEmailsByIdsSuccess extends UIState {
   List<Object?> get props => [presentationEmails, updateCurrentThreadDetail];
 }
 
+class PreloadEmailsByIdsSuccess extends GetEmailsByIdsSuccess {
+  PreloadEmailsByIdsSuccess(super.presentationEmails);
+}
+
 class GetEmailsByIdsFailure extends FeatureFailure {
   GetEmailsByIdsFailure({
     super.exception,

lib/features/thread_detail/domain/state/get_thread_by_id_state.dart

@@ -21,6 +21,10 @@ class GetThreadByIdSuccess extends UIState {
   List<Object> get props => [emailIds, updateCurrentThreadDetail];
 }
 
+class PreloadEmailIdsInThreadSuccess extends GetThreadByIdSuccess {
+  PreloadEmailIdsInThreadSuccess(super.emailIds);
+}
+
 class GetThreadByIdFailure extends FeatureFailure {
   GetThreadByIdFailure({
     super.exception,