feat(mobile): add album description functionality (#18886)

* feat(mobile): add album description functionality

- Introduced a new optional `description` field in the `Album` entity.
- Updated `AlbumViewerPageState` to manage `editDescriptionText`.
- Created `AlbumDescription` and `AlbumViewerEditableDescription` widgets for displaying and editing album descriptions.
- Enhanced `CreateAlbumPage` to include a description input field.
- Implemented backend support for updating album descriptions in `AlbumApiRepository` and `AlbumService`.
- Updated sync logic to handle album descriptions during data synchronization.
- Adjusted UI components to accommodate the new description feature.

* fix dart analysis error

* remove comment that shouldn't be there

* Album header styling

* fix: disable edit after album creation

---------

Co-authored-by: Alex <alex.tran1502@gmail.com>

mobile/lib/widgets/album/album_viewer_appbar.dart

@@ -18,6 +18,7 @@ class AlbumViewerAppbar extends HookConsumerWidget
     super.key,
     required this.userId,
     required this.titleFocusNode,
+    required this.descriptionFocusNode,
     this.onAddPhotos,
     this.onAddUsers,
     required this.onActivities,
@@ -25,6 +26,7 @@ class AlbumViewerAppbar extends HookConsumerWidget
 
   final String userId;
   final FocusNode titleFocusNode;
+  final FocusNode descriptionFocusNode;
   final void Function()? onAddPhotos;
   final void Function()? onAddUsers;
   final void Function() onActivities;
@@ -48,6 +50,7 @@ class AlbumViewerAppbar extends HookConsumerWidget
 
     final albumViewer = ref.watch(albumViewerProvider);
     final newAlbumTitle = albumViewer.editTitleText;
+    final newAlbumDescription = albumViewer.editDescriptionText;
     final isEditAlbum = albumViewer.isEditAlbum;
 
     final comments = album.shared
@@ -277,20 +280,37 @@ class AlbumViewerAppbar extends HookConsumerWidget
       if (isEditAlbum) {
         return IconButton(
           onPressed: () async {
-            bool isSuccess = await ref
-                .watch(albumViewerProvider.notifier)
-                .changeAlbumTitle(album, newAlbumTitle);
-
-            if (!isSuccess) {
-              ImmichToast.show(
-                context: context,
-                msg: "album_viewer_appbar_share_err_title".tr(),
-                gravity: ToastGravity.BOTTOM,
-                toastType: ToastType.error,
-              );
+            if (newAlbumTitle.isNotEmpty) {
+              bool isSuccess = await ref
+                  .watch(albumViewerProvider.notifier)
+                  .changeAlbumTitle(album, newAlbumTitle);
+              if (!isSuccess) {
+                ImmichToast.show(
+                  context: context,
+                  msg: "album_viewer_appbar_share_err_title".tr(),
+                  gravity: ToastGravity.BOTTOM,
+                  toastType: ToastType.error,
+                );
+              }
+              titleFocusNode.unfocus();
+            } else if (newAlbumDescription.isNotEmpty) {
+              bool isSuccessDescription = await ref
+                  .watch(albumViewerProvider.notifier)
+                  .changeAlbumDescription(album, newAlbumDescription);
+              if (!isSuccessDescription) {
+                ImmichToast.show(
+                  context: context,
+                  msg: "album_viewer_appbar_share_err_description".tr(),
+                  gravity: ToastGravity.BOTTOM,
+                  toastType: ToastType.error,
+                );
+              }
+              descriptionFocusNode.unfocus();
+            } else {
+              titleFocusNode.unfocus();
+              descriptionFocusNode.unfocus();
+              ref.read(albumViewerProvider.notifier).disableEditAlbum();
             }
-
-            titleFocusNode.unfocus();
           },
           icon: const Icon(Icons.check_rounded),
           splashRadius: 25,