Refactor configuration setup and error handling

- Added custom configuration sources to the builder.
- Removed Azure Key Vault integration for secret management.

Surge365.MassEmailReact.API/Program.cs

@@ -22,17 +22,7 @@ builder.AddCustomConfigurationSources();
 WebApplication? app = null;
 try
 {
-    var keyVaultName = builder.Configuration["KeyVaultName"] ?? "";
-    if (!string.IsNullOrEmpty(keyVaultName))
-    {
-        var keyVaultUri = $"https://{keyVaultName}.vault.azure.net/";
-        builder.Configuration.AddAzureKeyVault(
-            new Uri(keyVaultUri),
-            new DefaultAzureCredential(),
-            new SurgeKeyVaultSecretManager()
-        );
-    }
-    builder.Services.AddSingleton<ILoggingService, LoggingService>();
+    builder.AddCustomConfigurationSources();
 
     var jwtKey = Encoding.UTF8.GetBytes(builder.Configuration["Jwt:Secret"]!);
     builder.Services.AddAuthentication(options =>
@@ -57,7 +47,6 @@ try
 
     builder.Services.AddHttpContextAccessor();
 
-
     Factory.RegisterDefaultServices(builder.Services,
         adminContextProvider: provider =>
         {
@@ -138,8 +127,6 @@ try
     app.UseAuthorization();
 
     app.MapControllers();
-
-
 }
 catch (Exception ex)
 {