"Outlook error" handling for 429 status code.

Wino.Core/Synchronizers/Errors/Outlook/OutlookRateLimitHandler.cs

@@ -0,0 +1,38 @@
+using System;
+using System.Threading.Tasks;
+using Microsoft.Graph.Models.ODataErrors;
+using Microsoft.Kiota.Abstractions;
+using Serilog;
+using Wino.Core.Domain.Enums;
+using Wino.Core.Domain.Interfaces;
+using Wino.Core.Domain.Models.Synchronization;
+
+namespace Wino.Core.Synchronizers.Errors.Outlook;
+
+/// <summary>
+/// Handles Microsoft Graph throttling responses for Outlook synchronization.
+/// </summary>
+public class OutlookRateLimitHandler : ISynchronizerErrorHandler
+{
+    private readonly ILogger _logger = Log.ForContext<OutlookRateLimitHandler>();
+
+    public bool CanHandle(SynchronizerErrorContext error)
+    {
+        return error.ErrorCode == 429 ||
+               (error.Exception is ODataError oDataError && oDataError.ResponseStatusCode == 429) ||
+               (error.Exception is ApiException apiException && apiException.ResponseStatusCode == 429);
+    }
+
+    public Task<bool> HandleAsync(SynchronizerErrorContext error)
+    {
+        _logger.Warning(error.Exception,
+            "Microsoft Graph rate limit hit for account {AccountName} ({AccountId}). Operation: {Operation}.",
+            error.Account?.Name, error.Account?.Id, error.OperationType ?? "N/A");
+
+        error.Severity = SynchronizerErrorSeverity.Transient;
+        error.Category = SynchronizerErrorCategory.RateLimit;
+        error.RetryDelay = TimeSpan.FromSeconds(10);
+
+        return Task.FromResult(true);
+    }
+}