Refactored all synchronizers to deal with some of the chronic issues.

Wino.Services/AccountService.cs

@@ -599,4 +599,24 @@ public class AccountService : BaseDatabaseService, IAccountService
 
         return account?.Preferences?.IsNotificationsEnabled ?? false;
     }
+
+    public async Task UpdateLastFolderStructureSyncDateAsync(Guid accountId)
+    {
+        var account = await GetAccountAsync(accountId);
+        if (account == null) return;
+
+        account.LastFolderStructureSyncDate = DateTime.UtcNow;
+        await Connection.UpdateAsync(account, typeof(MailAccount)).ConfigureAwait(false);
+    }
+
+    public async Task<bool> ShouldSyncFolderStructureAsync(Guid accountId, TimeSpan syncInterval)
+    {
+        var account = await GetAccountAsync(accountId);
+        if (account == null) return true;
+
+        if (!account.LastFolderStructureSyncDate.HasValue)
+            return true;
+
+        return DateTime.UtcNow - account.LastFolderStructureSyncDate.Value > syncInterval;
+    }
 }

Wino.Services/MailService.cs

@@ -1124,6 +1124,18 @@ public class MailService : BaseDatabaseService, IMailService
         return new GmailArchiveComparisonResult(addedMails, removedMails);
     }
 
+    public async Task<IEnumerable<string>> GetRecentMailIdsForFolderAsync(Guid folderId, int count)
+    {
+        var recentMails = await Connection.Table<MailCopy>()
+            .Where(a => a.FolderId == folderId)
+            .OrderByDescending(a => a.CreationDate)
+            .Take(count)
+            .ToListAsync()
+            .ConfigureAwait(false);
+
+        return recentMails.Select(m => m.Id);
+    }
+
     public async Task<List<MailCopy>> GetMailItemsAsync(IEnumerable<string> mailCopyIds)
     {
         if (!mailCopyIds.Any()) return [];