fix(server): do not reset fileCreatedDate (#15650)

When marking an offline asset as online again, do not reset the
fileCreatedAt value. This value contains the "true" date, copied
from exif.dateTimeOriginal. If we overwrite this value, we'd need
to run the metadata extraction job again. Instead, we just leave
the old (and correct) value in place.

fixes #15640

server/src/services/library.service.ts

@@ -511,7 +511,6 @@ export class LibraryService extends BaseService {
       await this.assetRepository.updateAll([asset.id], {
         isOffline: false,
         deletedAt: null,
-        fileCreatedAt: mtime,
         fileModifiedAt: mtime,
         originalFileName: parse(asset.originalPath).base,
       });