fix: normalize Resend API key configuration

backend/src/Socialize.Api/Infrastructure/Emailer/Services/ResendEmailSender.cs

@@ -20,18 +20,24 @@ public class ResendEmailSender : IEmailSender
         _httpClient = httpClientFactory.CreateClient();
         _options = options.Value;
 
-        if (string.IsNullOrWhiteSpace(_options.ApiKey))
+        string apiKey = NormalizeApiKey(_options.ApiKey);
+        string fromEmail = _options.FromEmail?.Trim() ?? string.Empty;
+
+        if (string.IsNullOrWhiteSpace(apiKey))
         {
             throw new InvalidOperationException("Emailer:ApiKey is required when using Resend email delivery.");
         }
 
-        if (string.IsNullOrWhiteSpace(_options.FromEmail))
+        if (string.IsNullOrWhiteSpace(fromEmail))
         {
             throw new InvalidOperationException("Emailer:FromEmail is required when using Resend email delivery.");
         }
 
+        _options.ApiKey = apiKey;
+        _options.FromEmail = fromEmail;
+
         _httpClient.DefaultRequestHeaders.Authorization =
-            new AuthenticationHeaderValue("Bearer", _options.ApiKey);
+            new AuthenticationHeaderValue("Bearer", apiKey);
 
         _httpClient.DefaultRequestHeaders.Accept.Add(
             new MediaTypeWithQualityHeaderValue("application/json"));
@@ -53,4 +59,16 @@ public class ResendEmailSender : IEmailSender
                 $"Resend email failed: {response.StatusCode} - {body}");
         }
     }
+
+    private static string NormalizeApiKey(string? apiKey)
+    {
+        string normalized = apiKey?.Trim().Trim('"', '\'') ?? string.Empty;
+        const string bearerPrefix = "Bearer ";
+        if (normalized.StartsWith(bearerPrefix, StringComparison.OrdinalIgnoreCase))
+        {
+            normalized = normalized[bearerPrefix.Length..].Trim();
+        }
+
+        return normalized;
+    }
 }