Add Reply-To diagnostic logging to GetEmailFromAsync

Logs a Warning when no Reply-To email is configured for a company
(so the logs show why replies land at the platform sender address)
and a Debug entry when one is set, making future send issues
diagnosable without needing the SendGrid Activity API.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/PowderCoating.Infrastructure/Services/NotificationService.cs

@@ -1535,7 +1535,15 @@ public class NotificationService : INotificationService
             .AsNoTracking()
             .FirstOrDefaultAsync(p => p.CompanyId == companyId && !p.IsDeleted);
 
-        return (prefs?.EmailFromAddress, prefs?.EmailFromName);
+        var email = prefs?.EmailFromAddress;
+        var name  = prefs?.EmailFromName;
+
+        if (string.IsNullOrWhiteSpace(email))
+            _logger.LogWarning("No Reply-To email configured for company {CompanyId} — outgoing emails will show platform sender as reply address", companyId);
+        else
+            _logger.LogDebug("Reply-To for company {CompanyId}: {ReplyToEmail}", companyId, email);
+
+        return (email, name);
     }
 
     /// <summary>